How do you solve the system $-2x+15y=-24, 2x+9y=24$ ?

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Answer 1 · 2016-11-30T12:37:30

$x = 12$ and $y = 0$

Step 1) Solve the first equation for $x$ :

$-2x + 15y - 15y = -24 - 15y$

$-2x = -24 - 15y$

$(-2x)/-2 = (-24 - 15y)/-2$

$x = 12 +15/2y$

Step 2) Substitute $12 + 15/2y$ for $x$ in the second equation and solve for $y$ :

2(12 + 15/2y) + 9y = 24#

24 + 15y + 9y = 24#

$24 + 24y = 24$

$24 - 24 + 24y = 24 - 24$

$24y = 0$

#(24y)/24 = 0/24$

$y = 0$

Step 3) Substitute $0$ for $y$ in the solution to the equation in Step 1) and calculate $x$ :

$x = 12 + (15/2 * 0)$

$x = 12 + 0$

$x = 12$

How do you solve the system -2x+15y=-24, 2x+9y=24-2x+15y=-24, 2x+9y=24?