Question

Solve the system of equations. y =9x y =2x + 63

Answer 1

y=2x+7
y=9x+8
From (1),
x= (y-7)/2
Substituting value of x in eqn (2) we get,
y= 9.(y-7)/2 + 8

Answer 2

y=9x and
y=2x+63

subsitute 9x for y

9x=2x+63
minus 2x from both sides
9x-2x=2x-2x+63
7x+0=63
7x=63
divide both sides by 7
7x/7=63/7
(7/7)x=9
(1)x=9
x=9

sub back to find y


y=9x
y=9(9)
y=81

(x,y)
(9,81)

the solution is (9,81)