Answer:
The 3 angles are 62 2/3, 44 2/.3 and 72 2/3 degrees.
Step-by-step explanation:
let x be the first angle then the the second angle is x - 18 and the third angle = x + 10
The 3 angles add up to 180 so:
x + x - 18 + x + 10 = 180
3x = 180 + 18 - 10 = 188
x = 188/3 = 62 2/3 degrees.
x - 18 = 44 2/3
x + 10 = 72 2/3.
Answer:
-30
Step-by-step explanation:
I'm assuming the equation is
. If it is not please tell me.
If we know the values of m and n, we can just substitute inside the expression.

Hope this helped!
Answer:
25
Step-by-step explanation:
he got an 80 so if that was his grade by answering 20 questions right then the correct answer would be 25 questions
The easiest way to solve this is by elimination.
3x - y = 6
6x + y = 21
Since you have a negative and positive y with the same coefficients (1), they cancel, and you add the other terms so it would look like:
9x = 27
Then solving for x leaves you with x = 3
Then you take the x value of three and plug it into to either of the equations, so
3(3) - y = 6
9 - y = 6
subtracting 9
-y = -3
then dividing by -1
y = 3
so the solution is x = 3 y = 3 or (3,3)
Answer:
(-2,3)
Step-by-step explanation:
Step 1. Isolate x for 3x + 5y = 9
3x + 5y - 5y = 9 - 5y
3x = 9 - 5y
3x/3 = 9/3 - 5y/3
x= (9-5y)/3
Step 2. Simplify
-3*((9-5y)/3) + 3y = 15
-3*((9-5y)/3) = 9 - 5y = -(-5 + 9) + 3y
-9+5y+3y
-9+8y = 15
Step 3 Isolate y for -9+8y=15
-9+8y+9=15+9
8y=24
8y/8 = 24/8
y=3
Step 4 Substitute y = 3
x = (9-5*3)/3
-(6/3) = (-2)
x = -2