Questions on Algebra: Expressions involving variables, substitution answered by real tutors!

Tutors Answer Your Questions about Expressions-with-variables (FREE)

Question 579922: What is the solution for these to expressions involving variables
2x-3y=6 and 3y-2x=-6?
I've tried the substitution and elimanation method and neither seem to work.
Click here to see answer by dfrazzetto(277)

Question 580080: If sailcloth costs $10 per square foot, what is the cost of a new mainsail?
Before solving this problem let's review the
Pythagorean Theorem. This theorem relates
the lengths of the three sides of a right triangle.
A right triangle has a 90º angle. The side opposite
the 90º angle is called the hypotenuse and the
other sides are called legs.

The Pythagorean theorem states that for every right triangle,
the sum of the squares of the legs is equal to the square of the hypotenuse.

a2 + b2 = c2

Now solve the problem:

The mainsail on the sailboat shown below is a right triangle in which the
hypotenuse is called the leech. If sailcloth costs $10 per square foot,
what is the cost of a new mainsail?

Hint: To find the cost of the sail, you need to know the area of the sail. You must
first find the base (x) of the mainsail using the Pythagorean Theorem. Once
you have found the value of x then find the area of the sail by using the
formula for the area of a triangle: 1/2 base times height; A= ½bh .

x

Leech IS 13 ft

12 ft

tHIS IS A HUGE PART OF MY GRADE!! I NEED HELP.. i DO NOT EVEN KNOW HOW TO WRITE IT OUT.
Click here to see answer by Alan3354(30993)

Question 580232: m^a-2 p^a-3
_____________
m^a/5 p^-2a
Click here to see answer by stanbon(57377)

Question 580247: Solve each system by substitution
Y=x-5
Y=4x-8
Need to learn how to help my daughter work these problems so I can be on the same page with her.
We need step by step directions if possible pretty please, it would've grealy appreciated...THANK YOU
Solve each system by elimination
4x-2y=-8
-4x+5y=14
Click here to see answer by jim_thompson5910(28595)

Question 580598: Rl Yamaha raven going 181 mph how long will it take to travel 8 miles
Click here to see answer by josmiceli(9687)

Question 580770: F = 9/5(C) + 32 for C
Click here to see answer by Alan3354(30993)

Question 580780: A = P + Prt (Simple interest formula) for t
Click here to see answer by Alan3354(30993)

Question 580845: I have tried this problem over and over but each time my professor tells me that it's wrong. Can you help me figure out what i am doing wrong?
3/n + 6/n - 1/4
My answers so far:
9/n - 1/4
36/8n - 1/4
36/5n
Click here to see answer by Alan3354(30993)

Question 581524: the expression 4 cubed times 4 to the 5th power is equivalent to what

Click here to see answer by Earlsdon(6287)

Question 581524: the expression 4 cubed times 4 to the 5th power is equivalent to what

Click here to see answer by algebrahouse.com(1079)

Question 581653: solve using substitution method
7x+y=51
8x-5y=3

Click here to see answer by jim_thompson5910(28595)

Question 582436: The coefficient of 9(14)P is _____.
A. 9
B. 14
C. 126
Click here to see answer by jim_thompson5910(28595)

Question 582442: Simplify.
(m+13)- (p+25)
Click here to see answer by jim_thompson5910(28595)

Question 582398: please help me to grasp the concept of solving with elimination method.
-3x+4y=1
-6+6y=-3
4x-8y=48
11x+3y=105.5
8x+11y=-50
-32x-44y=-200
Click here to see answer by ankor@dixie-net.com(15657)

Question 582894: A plane that can normally travel at 250 mph in calm air is flying onto a headwind of 25 mph. How far can the plane fly in 3 hours?
Click here to see answer by ankor@dixie-net.com(15657)

Question 583938: How do I solve for x and y when solving systems of equations by substitution
y=6x-11
-2x-3y=-7
if I use the y=6x-11 into -2x-3y=-7
-2x-3(6x-11)=-7
do I multiply -3 and 6x?
Click here to see answer by ankor@dixie-net.com(15657)

Question 584848: 7x+4y=-34
x=-2-2y
7(-2-2y)=4y=-34
-14-14y+4y=-34
-10y+-14= could you show me step by step please?
how did they get y=2
x=-6
Click here to see answer by Alan3354(30993)

Question 584933: 5 times a number ,x, decreased by y
Click here to see answer by jim_thompson5910(28595)

Question 585042: a-[b-c+a-{b-(c-a-a+b)}]
Click here to see answer by Edwin McCravy(8909)

Question 585111: 2x+4y=-3
2x-y=7
y=2x-7
2x+4y=-3
2x+4(2x-7)=-3
2x+8x-28=-3 can you show me step by step please? their answer was 5/2,-2?
Click here to see answer by richwmiller(9143)

Question 585127: 9x+ y=20
9x+16y=14 please help me?
Click here to see answer by Alan3354(30993)

Question 585135: ( (6 + 4)(6 + 4)) - (25 x 2)? what is the answer?
Click here to see answer by richwmiller(9143)

Question 585144: 9x+ y=20
9x+16y=14 please help me?
Click here to see answer by Alan3354(30993)

Question 585142: How do you simplify 3/4(6m-20n+7)
Click here to see answer by Alan3354(30993)

Question 585183: 0.3x-0.2y=4
0.5x+0.5y=-45/17
3x-2y=40
5x+5y=-450/17
15x-10y=200
15x-15y=1350/17
_________________
-25y= 4750/17 dont know how they got this?
y=-190/17
3x-2(-190/17)=40
100/17
Solution 100/17,-190/17
Click here to see answer by stanbon(57377)

Question 585119: y=2x-6
2x2y=-4
2x+4(2x-6)=-4
2x+8x-24=-4 help please?
Click here to see answer by Alan3354(30993)

Question 585445: -9x+ y=20
9x+16y=14
y=20+-9
9x + 16 (20+-9x)=14
9x+320=144x=14
153x+320=14 I understand up to here

x= -2 dont understand how they got these answers could you show me step by step please?
y= 2
Click here to see answer by jim_thompson5910(28595)

Question 585482: 2x2y=-3
2x-y=5
2x+2(2x-5)=-3
2x+4x-10=-3
6x=7
x=7/6 I understand up to here but then I am confused they got solution 7/6,-8/3 can you please show me step by step please?
Click here to see answer by Alan3354(30993)

Question 585874: 2x/3 + y/4 =2
x/3 - y/9 = 9 could you please help with this problem
Click here to see answer by scott8148(6628)

Question 588314: how do i solve x-y=2?

Click here to see answer by ankor@dixie-net.com(15657)

Question 589191: Find two consecutive integers such that the sum of their squares is 61
Click here to see answer by AnlytcPhil(1277)

Question 589191: Find two consecutive integers such that the sum of their squares is 61
Click here to see answer by mathhelp@(10)

Question 589191: Find two consecutive integers such that the sum of their squares is 61
Click here to see answer by Alan3354(30993)

Question 589190: Find three consecutive positive integers such that the product of the second and third integers is 20
Click here to see answer by Alan3354(30993)

Question 589652: How do I solve for f when h=5f, for f? f=??
Click here to see answer by ankor@dixie-net.com(15657)

Question 590022: Solve the formula for the indicated variable.
(9/5)C + 32 = F
Solve for C
Click here to see answer by stanbon(57377)

Question 590023: Solve the formula for the indicated variable.
A=1/2bh
Solve for h
Click here to see answer by Alan3354(30993)

Question 590119: Solve the system by substitution or elimination. If the system is inconsistent or has dependent equations, say so.
x+y=12
y=4x-3
A) 3,9 B) 4,9 C) 2,12 D) 9,3
Click here to see answer by Alan3354(30993)

Question 590123: Solve the system by substitution or elimination. If the system is inconsistent or has dependent equations, say so.
y= -4/5x
4x -5y= -6
A) -3/4, 3/5 B) 3/4, 3/5 C) -3/4, -3/5 D) 0; inconsistent system
Click here to see answer by Alan3354(30993)

Question 590639: A number plus the reciprocal of the number is 5/4 of the number. What is the number?
Click here to see answer by bucky(2189)

Question 590116: Tell how many solutions the system has. do not actually solve.
5x+4y=-1
25x+20y=-5
Click here to see answer by bucky(2189)

Question 590798: I am having a terrible time doing word problems in algebra, simple for some but not for me. Could someone please help with two problems, thank you very much.
A university bookstore recently sold a wire bound graph-paper notebook for $2.50, and a college-ruled notebook for $2.30. At the start of spring semester, a combination of 50 of these notebooks were sold for a total of $118.60. How many of each type were sold?
A bricklayer and an electrician together spend 90 hours working on a new house. If the bricklayer earns $12 per hour, the electrician earns $16 an hour, and the owner pays them a total of $1350 for their work, how many hours does each worker spend on the house?
Click here to see answer by Theo(3464)

Question 591005: y=5x
2x+3y=34
Click here to see answer by edjones(7569)

Question 123811: Problem Solving With Systems of A line: How to Solve
The difference of the measures of two supplementary angles is 35*. Find both angle measures. The sum they add up to is 180*.
Click here to see answer by eschwartz(9)

Question 591747: u+2=4
Click here to see answer by jim_thompson5910(28595)

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