Answer:
a=8
b=17
Step-by-step explanation:
Isoceles means we will have 2 congruent sides in this triangle.
So it appears we are to assume it is sitting on its base which means that other side has measurement ax+9 as well
So we have the sum of the 3 sides is the perimeter.
That means we have the equation:
(ax+9)+(ax+9)+(4x+b)=20x+35
Combine like terms:
(a+a+4)x+(9+9+b)=20x+35
(2a+4)x+(18+b)=20x+35
This implies 2a+4=20 and 18+b=35.
2a+4=20
Subtract 4 on both sides:
2a=16
Divide both sides by 2:
a=8
18+b=35
Subtract 18 on both sides:
b=17
So a=8 and b=17.