Those are vertical angles
First you would start getting the denominators to the same number and you could do this by multiplying 9/10 by 4, and 7/8 by 5 to get the denominators to 40 and when you add the fractions you get 71/40 so the answer would be D. About 2
Answer:


Step-by-step explanation:

Multiply both sides of the equation by 5.
5 ·
·
5 · 4
Simplify both sides of the equation.

Subtract 10 from both sides of the equation.

Divide each term by 2 and simplify.

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Substitute x for 6

Multiply 3 · 6

Add 18 + 9

Divide
÷ 27
9 = 9
-5 times -5= 25
because the negative times negative=positive
Whoever worded question made tha shi so confusing