*I'll be reviewing a*

**New York State Regents Exam**Question every day from now until the Regents exams begin next month. At least, that is the plan.### August 2014, Questions 34

**34.** *
The formula for the area of a trapezoid is A = (1/2)h(b _{1} + b_{2}).Express b_{1} in terms of A, h, and b_{2}.
*

*The area of a trapezoid is 60 square feet, its height is 6 ft, and one base is 12 ft. Find the number of feet in the other base.
*

You want to isolate the variable we want to solve for, in this case b_{1}:

**A = (1/2)h(b**

_{1}+ b_{2})*Multiply by 2:*2A = h(b

_{1}+ b

_{2})

*Divide by h:*2A/h = b

_{1}+ b

_{2}

*Subtract b*(2A/h) - b

_{2}from both sides:_{2}= b

_{1}

**b**

_{1}= (2A/h) - b_{2}To find the answer to the second part, substitute the values you have into the equation you just created, and evaluate.

**b _{1} = (2A/h) - b_{2} ** = (2(60)/6) - 12 = 120/6 - 12 = 20 - 12 = 8

The other base is 8 ft.

Any questions?

If anyone in Brooklyn is looking for an Algebra or Geometry Regents Prep tutor, send me a note. I have a couple of weekly spots available between now and June.

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