SAT Question f8fa0cf0: Linear Equations In One Variable answer and explanation with Desmos solution

It’s given that $9r=7(r+7)$. Applying the distributive property on the right-hand side of this equation yields $9r=7r+49$. Subtracting $7r$ from both sides of this equation yields $2r=49$. Dividing both sides of this equation by $2$ yields $r=\frac{49}{2}$. Therefore, the solution to the given equation is $\frac{49}{2}$. Note that 24.5 and 49/2 are examples of ways to enter a correct answer.