<span /><span>TLDR: Equation is 5(10 + x) = 6x. x = 50, so Sheila deposited $50 each 6 trips. Sherri deposited $60 each 5 trips. Both of them deposited $300 in total.
</span>Sherri deposited $10 more into her bank account than Sheila each 5 times. Expression: 5(x + 10).
Sheila deposited money 6 times
Expression: (6)(x) or 6x
Put it all together and the equation is 5(x+10)=6x.
Solve by distributing the 5 on the right side of the equation 5(x+10) to get 5x + 50 = 6x. Subtract 5x on both sides of equation. 5x - 5x + 50 = 6x - 5x to get 50 = 1x. Divide by 1 on each side to isolate the variable. x = 50. Sheila paid $50 in each of her 6 deposits, so she deposited $300 in total. Check the equation by replacing x with 50.
Sherri paid $60 in each of her 5 deposits because 50 + 10 is 60. 60 by 5 is also $300.
Answer:
Step-by-step explanation:

Answer: Choice A) AA postulate; 18
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Work Shown:
The triangles are similar to each other due to the AA (angle angle) postulate. The top angles are overlapping or shared angles. So that's the first pair. The second pair of angles is either bottom pair of angles, from the fact that corresponding angles are congruent. This is only true if the lines are parallel.
Due to the similar triangles, we can set up the proportion and solve for x
8/(8+4) = 12/x
8/12 = 12/x
8*x = 12*12 ... cross multiply
8x = 144
x = 144/8
x = 18