3x = -5y -------------- (1)
6x - 7y = 17 --------- (2)
From (1):
3x = -5y
x = -5/3 y ---------- sub into (2)
6 (-5/3 y) - 7y = 17
-10y - 7y = 17
-17y = 17
y = -1 ------------ Sub into (1)
3x = -5 (-1)
3x = 5
x = 5/3
Ans: x = 5/3, y = -1
Sole for f by simplifying both sides of the equation then isolating the variable so that means f=-40 over 3 for number one
for the second equation you do the same thing you did for number one and the answer will be
b=8
x + x + 3 + x - 8
3x - 5 = 55
3x = 60, x = 20
Since we put Julie as x, we put Janet at x + 3, and the brother is x - 8 (8 years younger)
Julie is 20
Janet (x + 3) = (20 + 3) = 23
Brother(x - 8) = (20 - 8) = 12
