Question

I'm supposed to write the equation of the line, in standard form, that has an x-intercept of 2 and is parallel to 2x + y = -5. Can someone help me through this problem?

Answer 1

we need to find the slope of 2x + y = -5...because a parallel line will have the same slope.
Do you know how to find the slope of that equation ?

Answer 2

Yes you subtract y2-y1/x2-x1?

Answer 3

no....you can do it that way if you have 2 sets of points..but you do not. So we must put the equation in y = mx + b form and m will be your slope. Can you do that ?

Answer 4

That's what I thought but how would I put it into y=mx+b form? Would I subtract 2x from both sides?

Answer 5

yes...that is exactly what you would do.

Answer 6

Meaning that the slope would be 2?

Answer 7

not quite....your subtracting 2x from both sides
2x + y = -5
2x - 2x + y = -2x - 5
y = -2x - 5
meaning the slope is -2.
understand so far ?

Answer 8

Yeah I've got it

Answer 9

now we will use y = mx + b
slope(m) = -2
(2,0)....x = 2 and y = 0
now we sub
0 = -2(2) + b
0 = -4 + b
4 = b

so your parallel equation is : y = -2x + 4
but we need it in standard form of Ax + By = C...

y = -2x + 4
2x + y = 4

check to see if x intercept is 2 by subbing in 0 for y
2x + 0 = 4
2x = 4
x = 2 (correct)

so your parallel equation in standard form where your x intercept is 2 is :
2x + y = 4

Answer 10

if you have any questions, ask them now

Answer 11

No, wow thank you, you explained it quite well :)