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24 votes
24 votes
Please write a linear equation that has m=-4 and has an x-intercept of (5,0)!

User Yannic
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2 Answers

15 votes
15 votes

We need to determine the value of the y-intercept for this equation. Let's start by finding all other information about the x-intercept.

If the x-intercept is x = 5, f(5) = 0. So, now let's solve for b.

f(5) = -4(5) + b
0 = -4(5) + b
0 = -20 + b
0 + 20 = -20 + 20 + b
b = 20

We have m and b now, so:

y = -4x + 20

User Jeffld
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2.7k points
6 votes
6 votes

Answer:

If you use y = mx + b, your equation would be y = -4x + 20

Explanation:

M is always the slope, and to find the x-intercept, you just set y = 0 and in this case it would be 0 = -4x + 20. If you subtract 20 from both sides you get -20 = -4x and to find x, you just divide by -4 and get -20/-4, which equals 5. You're welcome :)

User Lentinant
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3.1k points