How do you solve this system of equations: $- 3 x - 5 y = 4; - 5 x - 4 y = 24$ $-3x - 5y = 4;- 5x - 4y = 24$ ?

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Answer 1 · 2018-04-25T02:34:57

$x = - 8$ $x=-8$ , and $y = 4$ $y=4$ .

Equation 1

$- 3 x - 5 y = 4$ $-3x-5y=4$

Equation 2

$- 5 x - 4 y = 24$ $-5x-4y=24$

I'm going to solve this by substitution.

First solve Equation 1 for x.

Equation 3

$x = - \frac{5 y + 4}{3}$ $x=-(5y+4)/3$

Next, substitute this expression for $x$ $x$ into Equation 2

Equation 4

$\frac{5 (5 y + 4)}{3} - 4 y = 24$ $(5(5y+4))/3-4y=24$

Now solve for $y$ $y$ .

$25 y + 20 - 12 y = 72$ $25y+20-12y=72$

$13 y = 52$ $13y=52$

$y = 4$ $y=4$

Now put this value for $y$ $y$ into Equation 3 to determine $x$ $x$ .

$x = - \frac{5 (4) + 4}{3} = - 8$ $x=-(5(4)+4)/3=-8$

How do you solve this system of equations: −3x−5y=4;−5x−4y=24-3x - 5y = 4;- 5x - 4y = 24?