Solve please?

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2 Answers
Jun 1, 2018

a= 5 and a = -5

Explanation:

Using the difference of two squares:
#a^2-b^2 = (a+b)(a-b)#

#a^2-25 = 0 => (a+5)(a-5)=0#
Using null factor law.
# a+5=0 #
#a = -5 #.
Or
# a-5=0 #
#a = 5#.

Jun 1, 2018

Is an incomplete second degree equation. See below for solution

Explanation:

We can apply the quadratic formula also but in this case is easy

#a^2-25=0# we can write

#a^2=25# (square root in both sides)

#a=+-sqrt25=+-5#

The solutions are #a=5# and #a=-5#