Question

(01.05)

Given the point (4, 5) and the slope of 6, find y when x = 24.

118

144

125

149

Answer 1

i got 125

Answer 2

I agree. But let's discuss HOW we obtain such a result.
If x increases from 4 (that's the 4 in the point (4,5)) to 24, the change in x is 20.
The change in y is thus (6/1)*20 (slope times change in x), or 120.
Since y=5 at the starting point (4,5), the final y value is 5+120, or 125.

Alternatively, using the point-slope formula for a straight line, and the given point and given slope, we could find an equation for the line passing through (4,5) with slope 6, substitute x = 24 (not 20), and calculate the final y value. If done correctly, that'll be 125, as before.