Adding any two positive numbers will result in another positive number.
For example:
7+3 = 10
The values 7, 3 and 10 are positive.
It is impossible to add 2 positive numbers to get a negative number.
m∠A + m∠B = 90, since the angles are complementary.
The question also tells us that m∠A = (2x + 10) and m∠B = (-x + 55)
So, all we have to do is input the angle's values into the first equation:
(2x+10) + (-x+55) = 90
Simplify:
x + 65 = 90
x = 25
Input the variable into the angles:
m∠A = 2(25) + 10 = 50 + 10 = <u>60°</u>
m∠B = -25 + 55 = <u>30°</u>
Plug in the point
1 = 10 - 4(6)
1 = 10 - 24
1 = -14, false
Solution: B
Using logarithmic laws: log(a) + log(b) = log(ab)
log₄ (x + 9) + log₄ (x + 21) = log₄ [(x + 9)(x + 21)] = 3
Since we want the equation in terms of x, the next intuitive step is take 4 to the power of both sides, because the left hand side will simplify easily.



Solving the quadratic we get:



BUT, for the logarithmic equation to be defined, x > -9, so x≠ -25
Thus, the only solution is x = -5.