Question

4x-5y=-15
7x-2y=21
X=
Y=

Answer 1

Answer:

The values of x and y to the given equations are x=5 and y=7

Step-by-step explanation:

Given equations are $4x-5y=-15\hfill (1)$

$7x-2y=21\hfill (2)$

To solve the given equations by elimination method :

Multiply the equation (1) into 2 we get

$8x-10y=-30\hfill (3)$

Multiply the equation (2) into 5 we get

$35x-10y=105\hfill (4)$

Now subtracting the equations (3) and (4) we get

$8x-10y=-30$

$35x-10y=105$

_________________

$-27x=-135$

$x=\frac{135}{27}$

Therefore x=5

Now substitute the value of x=5 in equation (1) we get

4(5)-5y=-15

20-5y=-15

-5y=-15-20

-5y=-35

$y=\frac{35}{5}$

Therefore y=7

The values are x=5 and y=7