How do i find this? i keep getting 31, but it should be 30

Solve this system of equations. 12x − 18y = 27 4x − 6y = 10

Does the function satisfy the hypotheses of the mean value theorem on the given interval? f(x) = 4x^2 + 3x + 4, [−1, 1] no, f is continuous on [−1, 1] but not differentiable on (−1, 1). no, f is not continuous on [−1, 1]. yes, f is continuous on [−1, 1] and differentiable on (−1, 1) since polynomials are continuous and differentiable on . there is not enough information to verify if this function satisfies the mean value theorem. yes, it does not matter if f is continuous or differentiable; every function satisfies the mean value theorem.

There are 45 questions on your math exam. you answered 810 of them correctly. how many questions did you answer correctly?