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you buy 5 pairs of jeans and 10 t-shirts for 140$.your friend buys 3 pairs of jeans and 5 t-shirts for $79. write and solve a system of linear of the equation by elimination

Respuesta :

Sarith

J = jeans

T = t-shirts

You: 5j + 10t = 140

Friend: 3j + 5t = 79

To use elimination in this problem, multiply the second equation by -2 so that 10t and 5t can cancel out:

5j + 10t = 140

-6j - 10t = -158

We are left with -j = -18 or j = 18

Substitute 18 into any equation. I'll use the first equation:

5(18) + 10t = 140

90 + 10t = 140

10t = 50

t = 5

ashley68541

Answer:

Jeans=18

Shirts=5

5j+10s=140

3j+5s=79

Step-by-step explanation:

1)  5j+10s=140                            multiply the bottom row by -2.

   -2(3j+5s=79)

2)  5j+10s=140                         add the top and bottom row.

   -6j-10s=-158

3) -j= -18                                  variable one found.

4) 5(-18) + 10s = 140              substitute j .

5) 90 + 10s = 140                 subtract 90.

6) 10s = 50                           divide by 10.

7) s = 5                                 variable 2 found.

8) 3(18) + 5(5) =79                 check for accuracy by substituting both.

9) 54 + 25 = 79                   solve.

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