SAT Question 9c0a0eca: Area and Volume answer and explanation with Desmos solution

Choice B is correct. The area, $A$, of a triangle is given by $A=\left(\frac{1}{2}\right)bh$, where $b$ is the length of a base of the triangle and $h$ is the corresponding height of the triangle. It's given that a triangle has a base length of $10$ centimeters and a corresponding height of $70$ centimeters. Substituting $10$ for $b$ and $70$ for $h$ in the formula $A=\left(\frac{1}{2}\right)bh$ yields $A=\left(\frac{1}{2}\right)\left(10\right)\left(70\right)$, or $A=350$. Therefore, the area, in square centimeters, of the triangle is $350$.