What’s the answer for liner combination to eliminate one of the variables. but which one of theses equations can replace 3x+5y=59

It says factor each expression 49x-28?

The lengths of two sides of a right triangle are given. find the length of the third side. round to the nearest tenth if necessary. a) y = 12/5x + 39/5 b) y = 5/12x + 5/39 c) y = 12/5x - 39/5 d) y = 5/12x - 5/39

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