WeBWorK Standalone Renderer

Which of the following are equations and which are expressions?

1. $3(x+5) = 6 - 2(x-5)$

2. $ax^2 + bx + c = 0$

3. $5(2x-1) + (5-x)(x+3)$

4. $3x - 2(5-x) + 7$

In order to get credit for this problem all answers must be correct.