Answer:
y = + or - sqrt (5) Please mark as the best answer.
Step-by-step explanation:
(2y)^2 = (2y)^1+1 = (2y)^1 * (2y)^1 = (2y)(2y) (When you multiply, exponents add)
2*2=4
y*y=y^2 (Use the same process again)
Put above back in the equation:
4y^2 + y^2 = 25 (Collect like terms. 4 and 1 both have y^2 so can add them)
5y^2 = 25 (Divide by 5 on both sides)
y^2 = 5 (Get rid of ^2 by sqrt symbol)
So,
y = + or - sqrt (5) (I normally write a smaller plus and then negative below. It is a + and a - because both +5 and -5 to the second power give 25.)
