Theresa earned scores of 88 points, 84 points, 88 points, and 91 points on four tests. what is the lowest score she can get on the fifth test and still finish with an average score of 90 points?
96 points
97 points
98 points
99 points

Option D is right

Step-by-step explanation:

Given that Theresa earned scores of 88 points, 84 points, 88 points, and 91 points on four tests

Thus total points she got in 4 tests = 88+84+88+91

= 351

If she has to obtain average score of 90 points,

then we have for 5 tests average should be 90

Hence total marks required = no of test *average

=5(90) =450

In 4 tests total =351

Minimum marks she must get in 5th test to get average score of 90 and above is

=450-351

=99

Option D

step-by-step explanation:

it would be 6xy and -16xy.