Is that the whole question?
Hey You!
25 * 300% = 75
25 + 75 = 100
The new amount is 100. =)
2y=-x+9
6y=3(-x+9)
3x-3(-x+9)=-15
3x-(-3x+27)=-15
3x+3x-27=-15
6x=-15+27
6x=12
x=2
2y=-2+9
2y=7
y=7/2
Answer is (2 ; 7/2)
So anytime we have a slope and want to find the slope of a perpendicular line, we just have to remember a perpendicular line's slope is the negative reciprocal (reciprocal means flip the fraction). So if we had a slope of 3/4, the slope perpendicular to it would be - 4/3.
First we need to find our slope, to do this we take the change in y over the change in x like so:
(15-12)/(4-7) = - 3/4
The slope perpendicular to this is 4/3.