Question

Solve the simultaneous equations by substitution
2x+7y=5
x+y=5

Answer 1

y=-1 and x=6

followed by the substitution method

Answer 2

x = 6

y = -1

Explanation:

i solved the second equation for 'y' to get 'y = 5 - x'

now i substituted that expression into the first equation for 'y'

2x + 7(5 - x) = 5

2x + 35 - 7x = 5

-5x = -30

x = 6

find 'y':

6 + y = 5

y = 5 - 6

y = -1