Question

Solve the system of equations. – 7x – 10y = 45 -3x - 5y = 25 x = Y =

Answer 1

Answer:

The solution is (-5, -2).

Step-by-step explanation:

We'll use "elimination by addition and subtraction."

Multiply the second row by -2.  Our system

– 7x – 10y = 45

-3x - 5y = 25

becomes:

– 7x – 10y = 45

+6x  + 10 y = -50

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  -x             =  5, so that x = -5.

Substituting -5 for x in the second equation results in

-3(-5) - 5y = 25, or  15 - 5y = 25.  This reduces to

-5y = 10, so that y must be -2.

The solution is (-5, -2).