Juanita, dueña de una librería, quiere saber cuánto va a obtener por la venta de 20 cuadernos.

Any is very appreciated! (picture is provided below)not sure how to do this at all won't lie

Ineed to know the answer to this algebra question.

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.