SOLUTION: the lin y=2x-10 meets the x-axis at point a. the line y=-2x+4 meets the y-axis at the point b. Find the equation of the line joining a and b

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Question 1198188: the lin y=2x-10 meets the x-axis at point a. the line y=-2x+4 meets the y-axis at the point b. Find the equation of the line joining a and b

Found 2 solutions by math_tutor2020, MathLover1:
Answer by math_tutor2020(3817) About Me  (Show Source):
You can put this solution on YOUR website!

Plug in y = 0 and solve for x to locate the x intercept.

y = 2x-10
0 = 2x-10
2x = 10
x = 10/2
x = 5
The x intercept is located at (5,0)
This is the location of point A.

Now plug in x = 0 to find the y intercept for the other linear equation
y = -2x+4
y = -2(0)+4
y = 4
The y intercept is (0,4) which is where point B is located.

We want to find the equation of the line through A(5,0) and B(0,4)
We need the slope


m+=+%28y%5B2%5D+-+y%5B1%5D%29%2F%28x%5B2%5D+-+x%5B1%5D%29

m+=+%284+-+0%29%2F%280+-+5%29

m+=+%284%29%2F%28-5%29

m+=+-4%2F5
We know the y intercept since this line goes through B(0,4)
The y intercept always occurs when x = 0.

We have m = -4/5 as our slope and b = 4 as the y intercept.

Therefore, the slope-intercept equation y+=+mx%2Bb becomes y+=+-expr%284%2F5%29x%2B4 which is the final answer.

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
if the line+y=2x-10 meets the x-axis at point+a, the point is (+a,0)
=>find x-intercept
+0=2x-10
+10=2x
+x=5
=> the point is (+5,0)
if the line y=-2x%2B4+meets the y-axis at the point b, the point is (+0,b)
=>find y-intercept
y=-2%2A0%2B4+
y=4+
the point is (+0,4)

to find the equation of the line joining a and+b, use points above to finnd a slope:
(+5,0), (+0,4)
m=%28y%5B2%5D-y%5B1%5D%29%2F%28x%5B2%5D-x%5B1%5D%29
m=%284-0%29%2F%280-5%29
m=-4%2F5
use point slope formula to find equation of a line
y-y%5B1%5D=m%28x-x%5B1%5D%29 ...........substitute coordiates of one point and a slope
y-0=-%284%2F5%29%28x-5%29
y=-%284%2F5%29x-%284%2F5%29%28-5%29
y=-%284%2F5%29x%2B4-> answer