Question

Write the equation of the line that contains the given point and has the given slope.

Answer 1

Y=mx+b   m- slope b- y-intercept(where the line crosses the y axis)
31=.5(15)+b plug in your values
31=7.5+b simplify
23.5=b    subtract 7.5 from both sides and your given b
y=.5x+23.5 plug everything into slope intercept form (y=mx+b)

Answer 2

Lets start with the slope intercept form to help find b using the slope given and the point given.

y=mx+b
(31)=.5(15)+b    substitution
31=7.5+b
31-7.5=7.5-7.5+b    additive inverse
23.5=b

Now we can substitute in the slope that was give m=.5 and the y-intercept(b) we found b=23.5:

y=.5x+23.5 (this is your answer)