Each question Sandra answers incorrectly changes her overall score by - points. Sandra's

overall score was -4 points, and then she answered the last question incorrectly. What

was Sandra's final score?

-5

Step-by-step explanation:

For each question Sandra answered incorrectly her overall score was changed by -1 point.

Her overall score was -4 before she attempted her last question incorrectly. Since a wrong answer gives her -1 point and her overall is -4

We add her overall and her point from last question which sums up to -5.

So sandras final score is -5

x = -3

y = -18

step-by-step explanation:

to solve by substitution, substitute one variable and solve for the other. then substitute again to find the remaining variable.

x-1/3(3x-9) = -3 since y=3x-9 substittute y.

x-1/3(3x-9)=-3

x + x +3 = -3

2x+3=-3

2x+3-3= -3-3

2x=-6

x=-3

substitute again into y=3x-9

y=3(-3)-9

y=-9-9

y=-18