Think of it like this
4x=2x+6
subtract two from 4
2x=6
x=3
Let's say David's age right now is x years
x + 6 = 2(x - 7)
x + 6 = 2x - 14
x = 20
Therefor David is 20 years old
The complete question in the attached figure
we know that
The Exterior Angle Theorem establishes that t<span>he measure of an exterior angle of a triangle equals to the sum of the measures of the two remote interior angles of the triangle.
so
the answer is the option</span><span>
A. the remote interior angles</span>
Answer:
principal square root
Step-by-step explanation:
Let
.
Then 
We have a negative square root for x, which is
and a nonnegative square root,which is 
The nonnegative square root is callled the principal square root .
Therefore the best complete to the statement;
A -------- is the nonnegative Square root of a number, is principal square root.