What is the value of x, when x2 + 5 = 21?

Mathematics

1 answer:

djverab [1.8K]3 years ago

4 0

Hey there!

$\bold{x^2+5=21}$
Firstly, subtract by the number $\bold{5}$ on each of your sides
$\bold{x^2+5-5=21-5}$
$\bold{Cancel:5-5}$ because it gives us the result of $\bold{1}$
$\bold{Keep:21-5}$ because it equals: $\bold{16}$
$\bold{x^2=16}$
Nextly, we have to take our square root
$\bold{x=}$ ± $\bold{\sqrt{16}}$
Solve the square root and you have found your answer
$\boxed{\boxed{\bold{Answer:x=4[or]x=-4}}}$ $\bold{\checkmark}$

Good luck on your assignment and enjoy your day!

~ $\bold{LoveYourselfFirst:)}$

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