Question

He equations9x-10y=6, 8x-10y=-23, 9x+10y=-16 and 8x+10y=13 are shown on the graph below.

Which is the approximate solution for the system of equations 8x-10y=-23 and 9x+10y=-16?

(–2.3, 0.5)
(–2.5, 1)
(–2.3, –0.5)
(–2.5, –1)

Answer 1

A (-2.3,0.5)

Explanation:

Answer 2

(-2.3,0.5)

Explanation:

Take the second equation we have y= (-16-9X)/10

Then, we will subtitute the value of y on the first equation

8X - 10(-16-9X/10)=-23

Because 10 is denominator, it will delate with the numeber 10 that is multipling the -16-9X. Then the equation is

8X-(-16-9X)=-23

then: 8x+16+9X=-23 So, 17x=-23-16 => X=-2.3

Then we put the value of X in the first equation so

9 (-2.3) -10y=-16 => 10y=-16+20.7

So, y=0.5