X= 1 y=4, x=2 y=8, x=3 y=12
After 5 tests, her average was 88. To have a seven-test average of 90, the total must be:

Her average after 5 tests was 88. Her total score on the 5 tests is:

Subtract:

Find the average by dividing by 2:

Her average must be 95
Let's do this in steps, show your work!
<u>#1. We need to move all terms to one side.</u>
<u>x^2 - 7x = 0</u>
<u>#2. Then factor out the common term x.</u>
<u>x(x - 7) = 0.</u>
<u>#3. Simplify to get..</u>
<u>x = 0, 7.</u>
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If you need help with any other question let me know.
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