How do you solve #y^2=49#?

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Answer 1 · 2015-12-06T13:17:43

The solutions are
#color(blue)(y=7, y=-7#

#y^2=49#

#y^2-49=0#

We will first factorise the expression.

As per property:

#color(blue)(a^2-b^2=(a-b)(a+b)#

So,
#y^2-49= color(blue)((y-7)(y+7)#

We now equate the factors to zero to find the solutions:

#y-7=0, color(blue)(y=7#

#y+7=0, color(blue)(y=-7#