So in class I have to do khan Academy

Solve the system by the elimination method. 3x - 2y - 7 = 0 5x + y - 3 = 0 to eliminate y, the lcm is 2. which of the following is the resulting equations? 1.3x - 2y - 7 = 0 5x + y - 3 = 0 2.3x - 2y - 7 = 0 -10x - 2y + 6 = 0 3.3x - 2y - 7 = 0 10x + 2y - 6 = 0

What is the equation and solution for the sentence? the sum of a number and thirty-one is one hundred thirteen. write the equation as n-31=113 and subtract 31 from both sides. the answer is 82. write the equation as n+31=113 and subtract 31 from both sides. the answer is 82. write the equation as n+31=113 and add 31 to both sides. the answer is 144. write the equation as n-31=113 and add 31 to both sides. the answer is 144.

What is the value of the expression below? (81^2)^1/8