Question

Find the solution of five times the square root of the quantity of x plus 7 equals negative 10 and determine if it is an extraneous solution.

x = −3; extraneous

x = −3; not extraneous

x = 11; extraneous

x = 11; not extraneous

Answer 1

-3 and extraneous

Answer 2

thanks!

Answer 3

Do you need me to explain why it is extraneous?

Answer 4

that would be nice

Answer 5

you there or nah?

Answer 6

\[5\sqrt{x+7}=-10\]\[\sqrt{x+7}=-2\]\[x+7=4\]\[x=-3\]
Now if we put x=-3 in the LHS of the original equation we get\[5\sqrt{x+7}=5\sqrt{4}\]
But \[\sqrt{4}=2\ and\ NOT\ -2!\] So the LHS=10 and not -10.

So the solution is extraneous.

Answer 7

ok

Answer 8

Sorry, typing equations takes a long time.

Answer 9

its all good thanks man!