Question

Can you please show your workings as I really don’t get this

Answer 1

Answer:

The solutions are x = 3, y=10  and x=7, y=30.

Step-by-step explanation:

We use substitution to solve this:

5x - y = 5

y = 5x - 5

Now substitute for y in the  second equation:

2y - x^2 = 11        Replace y by 5x - 5:-

2(5x - 5) - x^2 = 11

10x - 10 - x^2 = 11

x^2 - 10x + 21 = 0

(x - 3)(x - 7) = 0

x = 3 , 7.

Now we find the values of y corresponding to these 2 values of x:

When x = 3 ( using y = 5x - 5):

y = 5*3-5 = 10 and

when x = 7

y = 5*7 - 5 = 30.