Consider the function f(x) = 2x + 3x - 4 on the closed interval [-2, 1].Find the exact value of the slope of the secant

Consider the function f(x) = 2x² + 3x - 4 on the closed interval [-2, 1].Find the exact value of the slope of the secant line connecting (-2, f(-2)) and (1, f(1)).m =___________By the Mean Value Theorem, there exists c in (-2, 1) so that m = f'(c). Find all values of such c in (-2, 1). Enter exact values. If there is more than one solution, separate them by a comma.c=___________