Solve the system of linear equations using elimination. −2x − y = 3 −9x − y = 17
A) (2, 1) B) (2, −1) C) (−2, 1) D) (−2, −1)

x = -2 , y = 1

Step-by-step explanation:

Solve the following system:

{-2 x - y = 3 | (equation 1)

-9 x - y = 17 | (equation 2)

Swap equation 1 with equation 2:

{-(9 x) - y = 17 | (equation 1)

-(2 x) - y = 3 | (equation 2)

Subtract 2/9 × (equation 1) from equation 2:

{-(9 x) - y = 17 | (equation 1)

0 x - (7 y)/9 = -7/9 | (equation 2)

Multiply equation 2 by -9/7:

{-(9 x) - y = 17 | (equation 1)

0 x+y = 1 | (equation 2)

Add equation 2 to equation 1:

{-(9 x)+0 y = 18 | (equation 1)

0 x+y = 1 | (equation 2)

Divide equation 1 by -9:

{x+0 y = -2 | (equation 1)

0 x+y = 1 | (equation 2)

Collect results:

{x = -2 , y = 1

the final amount you will pay is $68.04.

the tip is determined by the pre-tax amount, so we calculate the tip based on the original bill, not after we've added sales tax.

to find the tip:

we can divide 54.00 by 100 to get 1% of 54. then we multiply that by 18.

54 / 100 = .54

.54 x 18 = 9.72

tip = 9.72$

to find the tax:

we can divide 54.00 by 100 to get 1% of 54. then we can multiply that by 8 to get 8%.

54 / 100 = .54

.54 x 8 = 4.32

tax= 4.32

now we can add the tip and tax to the bill to get our total.

54 + 9.72 + 4.32 = 68.04

total: $68.04

step-by-step explanation:

is there supposed to be a diagram or a graph for this one? ?

step-by-step explanation: