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What is the solution to the system of equations?

y = –3x – 2

5x + 2y = 15

(–40, 19)
(–19, 55)
(19, –40)
(55, –19)

Respuesta :

caylus
Hello,

Answer B

y=-3x-2 ==>3x+y=-2 (1)
5x+2y=15  (2)

(2)+2*(1)==>-x=19 ==> x=-19
y=-3*(-19)-2 ==>y=55
Sol={(-19,55)}

Reorganize the equations;
y+ 3x   =-2
2y+5x=15
-----------
Multiply equation I by two for y to have a common factor;
2y+6x=-4
2y+5x=15
--------------
x=-19
Replacing value of y in equation 1;
y+(3*-19)=-2
y-57=-2
y=55