Solve 2x + 5y = 20; 3x - 10y = 37 by elimination. how do you do this? -you!

Tickets to a science exposition cost $5.75 each for studentd and $7.00 for adults.how many students and adults went if the ticket charge was $42.75

Find the nonpermissible replacement for binthis expression.b2/5b +5

20 points plus brainliest andwer plus my hover hoard im v desperate ! evaluate the polynomial for x=-2 in the equation -3x^3+7x^2-7x-1 (simplify your answer)