Questions on Algebra: Quadratic Equation answered by real tutors!

Tutors Answer Your Questions about Quadratic Equations (FREE)

Question 78766: 1) A triangle has sides 2 X – 5, 3 X + 1, and 4 X + 2. Find the polynomial that represents its perimeter.
Click here to see answer by tutor_paul(490)

Question 78799: k^2=10
Click here to see answer by mathdoc314(58)

Question 78836: solve for p
4p^2-12p-91=0
our class is solving these type equations using the quadratic formula:
(-b +and- square root of b^2-4ac)/2a
so it would help a lot if you showed how to do it by plugging it into that formula.
i tried the problem once and got no real solution and then plugged it in again and got 6.5,-3.5. and i don't know which one's right because my notes say that the a has to equal 1... but im not sure if thats right or not
Click here to see answer by mathdoc314(58)

Question 78960: Problem:
Find the slope of the line through the following pair of points
(-5,-3) and (-5,2)

Click here to see answer by jim_thompson5910(28476)

Question 79004: Find the slope of the line graphed
(-3,-1)(-4,-3) (-5,-5)(-2,1)(-1,3)
Click here to see answer by checkley75(3666)

Question 79049: Problem:
The cost of producing a number of items x is given by C=mx+b , in which b is the fixed cost and m is the variable cost (the cost of producing one more item).
a) If the fixed cost is $40 and the variable cost is $10, write the cost equation
b) Graph the cost equation
c) The revenue generated from the sale of x items is given by R = 50x. Graph the revenue equation on the same set of axes as the cost equation.
d) How many items must be produced for the revenue to equal the cost (the break-even point)?

Click here to see answer by renevencer22(21)

Question 79048: Problem:
find the constant of variation k
m varies directly with n; m = 144 when n = 8

Click here to see answer by rapaljer(4667)

Question 79052: I need help to write an equation of a quadratic function whose graph is a parabola that has a vertex (-3,7) and that passes through the origin. Please.
Click here to see answer by funmath(2925)

Question 78996: Problem:
find the constant of variation k
m varies directly with n; m = 144 when n = 8

Click here to see answer by ankor@dixie-net.com(15624)

Question 79074: If the sides of a square are decreased by 3 cm, the area is decreased by 81 cm2. What were the dimensions of the original square?
Click here to see answer by checkley75(3666)

Question 78961:
Problem:
The cost of producing a number of items x is given by C=mx+b , in which b is the fixed cost and m is the variable cost (the cost of producing one more item).
a) If the fixed cost is $40 and the variable cost is $10, write the cost equation
b) Graph the cost equation
c) The revenue generated from the sale of x items is given by R = 50x. Graph the revenue equation on the same set of axes as the cost equation.
d) How many items must be produced for the revenue to equal the cost (the break-even point)?

Click here to see answer by renevencer22(21)

Question 78955: Problem:
The cost of producing a number of items x is given by C=mx+b , in which b is the fixed cost and m is the variable cost (the cost of producing one more item).
a) If the fixed cost is $40 and the variable cost is $10, write the cost equation
b) Graph the cost equation
c) The revenue generated from the sale of x items is given by R = 50x. Graph the revenue equation on the same set of axes as the cost equation.
d) How many items must be produced for the revenue to equal the cost (the break-even point)?

Click here to see answer by renevencer22(21)

Question 78993: Find the slope of the line through the given points
(2,4) and (6,-3)
Click here to see answer by checkley75(3666)

Question 79110: A rectangular garden is to be surrounded by a walkway of constant width. The garden’s dimensions are 30 ft by 40 ft. The total area, garden plus walkway, is to be 1800 ft2. What must be the width of the walkway to the nearest thousandth?
Click here to see answer by checkley75(3666)

Question 79089: c..
how do i complete the square for this one. i started it but i am confused.
Solve by completing the square: 2x^2+8x+3=0

this is how i started but i think i am wrong...

2x^2+8x+3=0
x^2+8x=(-3)/(2)
x^2+8x+(0.5 (8))^2=(-3)/(2)(0.5(8))^2
i don't know can someone help me i think i am doing it wrong...
Click here to see answer by josmiceli(9649)

Question 79120: please help me by factoring please?
4x^2-8x+3=5
Click here to see answer by jim_thompson5910(28476)

Question 79121: i need to solve by factoring
x^2-9x-4=6
Click here to see answer by jim_thompson5910(28476)

Question 79124: i am doing quadratic equations how do i solve by factoring?
(x-1)^2 = 7
Click here to see answer by ankor@dixie-net.com(15624)

Question 79117: Find the distance between (7, – 2) and (– 5, 3)
Click here to see answer by checkley75(3666)

Question 79075: The profit on a watch is given by P = X2 – 13 X – 80, where X is the number of watches sold per day. How many watches were sold on a day when there was a $50 loss?
Click here to see answer by 303795(595)

Question 79198: Use Quadratic Formula to solve problem; write all radicals in simplified form, and lowest terms:
x^2-24=0
Click here to see answer by sprolden(40)

Question 79243: how do i find two consecutive positive integers such that the sum of their squares is 85?
Click here to see answer by stanbon(57219)

Question 79243: how do i find two consecutive positive integers such that the sum of their squares is 85?
Click here to see answer by sprolden(40)

Question 79244: can someone help me solve by completing the square? i don't understand
2x^2+10x+11=0
Click here to see answer by stanbon(57219)

Question 79239: can you help me solve this equation for x?
25x^2=13
Click here to see answer by tutorcecilia(2152)

Question 79241: can you please check this for me? i am solving equation for x
2(x-5)^2=3
(x-5)^2=3/2
x-5=sqrt=sqrt/3
x=5sqrt/3
x=15/3sqrt/3
x=15sqrt/3
Click here to see answer by Edwin McCravy(8879)

Question 79245: help me someone please? i am so lost with this.
Construction. A garden area is 30 ft long and 20 ft wide. A path of uniform width is set around the edge. If the remaining garden area is 400ft^2, what is the width of the path?

Click here to see answer by stanbon(57219)

Question 79266: write the equation of the line with given slope and y-intercept. Then graph each line using the slope and y-intercept.
Slope: -3/4; y-intercept: (0,8)
Click here to see answer by checkley75(3666)

Question 79264: Find the slope and y-intercept of the line represented by each of the following equations.
2x-3y=6

Click here to see answer by checkley75(3666)

Question 79357: I can't seem to solve this problem to graph it, please help: y=x^2+3x+2
Click here to see answer by chitra(359)

Question 79378: can you help me solve by completing the square?
x^2-6x-3=0
Click here to see answer by stanbon(57219)

Question 79377: can someone help me solve for x please?
x^2+4x+4=7
Click here to see answer by jim_thompson5910(28476)

Question 79377: can someone help me solve for x please?
x^2+4x+4=7
Click here to see answer by Edwin McCravy(8879)

Question 79392: Please help answer this question:
The diagonal of a square television screen measures 18 inches. What is the length of the sides?
Click here to see answer by tutorcecilia(2152)

Question 79393: Please help with solving this problem--I'm lost.
When a ball is thrown, its height in feet h after t seconds is given by the equation h=vt-16t, where v is the initial upwards velocity in feet per second. If v=36 feet per second, find all values of t for which h=19 feet. Do not round any intermediate steps. Round your answers to 2 decimal places.
Thanks so much!!
Click here to see answer by ankor@dixie-net.com(15624)

Question 79399: I don't know what to do with this one. Please help. Here goes:
Find two positive numbers that differ by 2 and have a product of 20. Match your result to the correct answer below:
1-sqrt21, 3-sqrt21
-1+sqrt21, -1-sqrt21
-1+sqrt21, 1+sqrt21
-1+sqrt21, -3+sqrt21
Please help. Thanks
Click here to see answer by Earlsdon(6287)

Question 79403: I've got a word problem that has me stumped. Here it is:
Working together, Kent and Monica can paint the interior of a 2000 square-foot home in 10hours. If Kent paint the house by himself, it will take 2 hours longer than if Monica paints the home by herself. How long will it take each person to paint the house working alone?
Thanks so much!!
Click here to see answer by ankor@dixie-net.com(15624)

Question 79401: I really need help with this word problem. We're on Quadratic Equations so I'm assuming it relates. Here it is:
Sonya drives 160 miles at a certain speed. After stopping at a rest stop, she drives an additional 250 miles at a speed 15 mph slower than before the stop. If she drove 2 hours longer after the stop than before the stop, what was her speed before the stop? We need to round answer to the nearest tenth of a mile-per-hour.
Any help would be greatly appreciated. Thanks!
Click here to see answer by ankor@dixie-net.com(15624)

Question 79356: i really need some help to solve the following problem: y=x^2-9x+3 I tried to do it but kept getting different answers when I graphed it.
Click here to see answer by josmiceli(9649)

Question 79484: Problem:
Write the equation of the line L satisfying the given geometric conditions.
L has y-intercept (0, -3) and is parallel to the line with equation
y=2/3x+1
Click here to see answer by sprolden(40)

Question 79483: Problem:
Write the equation of the line with the given slope and y-intercept. then graph the line using the slope and y-intercept
Slope: -2; y-intercept: (0, 4)
You must show a graph to earn credit for this question.

Click here to see answer by sprolden(40)

Question 79480: Find the slope of any line perpendicular to the line through points (0, 5) and (-3, -4).
Click here to see answer by sprolden(40)

Question 79508: Problem:
Write the equation of the line with the given slope and y-intercept. The graph the line using the slope and y-intercept.
Slope: 5; y-intercept: (0, -2)
You must show a graph to earn credit for this question

Click here to see answer by checkley75(3666)

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