Please help me to find solutions to the following problems

8) Solve the following equation for z

T = 1 ( x- y +z)

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8

9) Divide and simplify as much as possible

x to the second power - 2x - 3/ 3x - 9

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x + 3 x - 1

10) SAMS RUNS 10 MILES IN 75 MINS, AT THE SAME RATE, HOW MANY MILES WOULD HE RUN IN 69 MINS?