Answer:
B
Step-by-step explanation:
sum means addition so n plus 9 would give you the sum of the both
The answer is 138
Because the angle is 180 and what I did was 2 x 21 = 42 and I did 180-42 equals to 138
Answer:
x = 100√3
Step-by-step explanation:
tan(30º) = x/300
x = 300 tan(30º)
x = 300/√3
x = 100√3
The variable "x" equals 7
Um.. Both of those equations are the exact same. Divide both sides of the first equation by 6. You get:

That is the exact same as the second equation. This system has an infinite number of solutions. 5x - 7y = -1 is a line, so basically every point on that line is a solution to the system.
For example,

and

would work, but so would

and