Uss addition or substitution to find the value of 'x' for this set of equations y=x-2 7y-4x=10

Aquadratic equation in standard from is written ax^2= bx+c, where a, b and c are real numbers and a is not zero?

Use the method of cylindrical shells to find the volume v generated by rotating the region bounded by the curves about the given axis. y = 7ex, y = 7e^-x, x = 1; about the y-axis

When i'm with my factor 5, my prodect is 20 .when i'm with my addend 6' my sum is 10.what number am i