Find the value of x in each case 2x 4x 6x
please help

Write an algebraic expression to match each statement a. four less than 8 times a number b. twice the difference of a number and six c. nine from a number squared

How long must $542 be invested at a rate of 7% to earn $303.52 in interest? in a easier way

Which is the focus of a parabola with equation y2=4x