exam Maths Puzzle Numerical Ability

t.21
solve and state the solution for the system by substitution.

x+3y=12
-5-4y=-16

t.22
solve and state the solution for the system by addition

3x+4y=-1
6x-2y=3

Read Solution (Total 0)

exam Other Question
The hypotenuse of a right triangle is 60 cm. If one leg is five centimeters longer than the other leg, what is the length of the legs? this problem is not in the book

I need to solve for x
1/a+1/x=1/b

i know i have to subtract 1/a 1/x=1/b-1/a
but do not know what to do next?