When i double my number and add eight, i get my number plus twelve. what is my number?

Afamily of five rents a kayak and splits the total time, k, equally. each family member spent less than 25 minutes kayaking. which values can be used to complete the math sentence below so that it accurately represents the situation? intro done

Solve the following simultaneous equation by using an algebraic method (either substitution or elimination) 2x + 3y=-4 4x-y=11

What effect would doubling all the dimensions of a triangular pyramid have on the volume of the pyramid? explain your reasoning.