Question

Using subsitution with systems of equations y=5x+8 y=8x+9

Answer 1

Hi there!

To solve this using substitution, we substitute the value of y in the equation.

5x + 8 = 8x + 9

Now, we simplify.

8 = 3x + 9
-1 = 3x

x = -1/3

We plug the value of x in,

y = 5 (-1/3) + 8
y = -1 2/3 + 8

y = 6 1/3

Hope this helps!

Answer 2

Y = 5x + 8 --------(1)

y = 8x + 9

=> 8x - y + 9 = 0 --------(2)

On Substituting equation (1) in (2), we get



8x - 5x - 8 + 9 = 0

=> 3x +1 = 0

=> x = - 1 /3

Now,

On Substituting the value of x in equation (1), we get

y = 5 (-1/3) + 8

y = - 5/3 + 8

y = (-5 + 24) /3

y = 19/3