I need me a guy bestfriend 14-18

Evaluate the expression for the given value of the variable 7a - 4a for a =8

Jenisey has $24 to spend on seven pencils. after buying them she had $10. how much did each pencil cost.?

Type the correct answer in the box. consider the system of linear equations below. rewrite one of the two equations above in the form ax + by = c, where a, b, and c are constants, so that the sum of the new equation and the unchanged equation from the original system results in an equation in one variable.