How do you solve $y^{2} = 49$ $y^2=49$ ?

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Answer 1 · 2015-12-06T13:17:43

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

$y^{2} = 49$ $y^2=49$

$y^{2} - 49 = 0$ $y^2-49=0$

We will first factorise the expression.

As per property:

$a^{2} - b^{2} = (a - b) (a + b)$ $color(blue)(a^2-b^2=(a-b)(a+b)$

So,
$y^{2} - 49 = (y - 7) (y + 7)$ $y^2-49= color(blue)((y-7)(y+7)$

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

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

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

How do you solve y^2=49y2=49y^2=49?