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Given the formula for the area of a trapezoid: $$\text{A}=\cfrac{1}{2}({b}_{1}+{b}_{2})h$$

...which one of the following is correct when solving for ${b}_{1}$?

${b}_{1}=\cfrac{A}{2h}-{b}_{2}$

${b}_{1}=\cfrac{2A}{h}-{2b}_{2}$

${b}_{1}=\cfrac{2A-{b}_{2}}{h}$

${b}_{1}=\cfrac{2A-{hb}_{2}}{h}$

${b}_{1}=2Ah-{b}_{2}$