Solve using completing the square x^2 - 8x + 16 = 25

All I need is the work shown I know the answer is {-1,9}

Question

Mathematics

Mcmillan

30 April, 04:45

Solve using completing the square x^2 - 8x + 16 = 25

All I need is the work shown I know the answer is {-1,9}

+4

Answers (1)

Know the Answer?

Gaven Singh · Answer 1

First we need to factor the left side. Since it is a perfect square (as is the process with completing the square, we know we can take half of the middle number along with x to be in the two parenthesis.

(x - 4) (x - 4) = 25

Now we simplify to show it as a square.

(x - 4) ^2 = 25

Next we take the square root of both sides

x - 4 = + / - 5

Note that we have plus or minus 5. This is because either square would give us positive 25. Now we add 4 to both sides

x = 4 + / - 5

4 + 5 = 9

4 - 5 = - 1

Solve using completing the square x^2 - 8x + 16 = 25All I need is the work shown I know the answer is {-1,9}

Solve using completing the square x^2 - 8x + 16 = 25

All I need is the work shown I know the answer is {-1,9}