How do you solve n^2-5=-4n25=4?

2 Answers
Sep 1, 2016

n=+-1n=±1

Explanation:

To solve a quadratic equation we require to equate it to zero.

The first step is therefore to add 4 to both sides of the equation.

rArrn^2-5+4=cancel(-4)+cancel(4)=0

rArrn^2-1=0" is the equation to be solved"

Now n^2-1 is a color(blue)"difference of squares"

rArr(n-1)(n+1)=0

solve: n-1=0rArrn=1

solve n+1=0rArrn=-1

Thus the solutions to the equation are n=+-1

Sep 4, 2016

n = +-1

Explanation:

Although this is a quadratic equation, it is a special case because there is no 'n' term.

Isolate the n^2 term.

n^2 = -4+5

n^2 = 1

n = +-1