Answer:
a = 18
Step-by-step explanation:
2(a-7)=a+4
Distribute 2 into left side: 2a -14 = a + 4
subtract a from both sides 2a-a-14 = a+4-a
Simplify: a - 14 = 4
Add 14 to both sides: a - 14 + 14 = 4 +14
Simplify: a = 18
If wanted, plug a into original to double check work:
plug in: 2 (18-7) = 18+4
do parenthesis first: 2 (11) = 18+4
do multiplication : 22 = 18+4
additions: 22 =22
a = 18 is correct.
Direct Variation equation: y=kx, k=y/x
42/14=3
k=3
y=3x
y=3(90)
y=270
Answer:
24
Step-by-step explanation:
Keep in mind that exterior angles are mentioned. So let's find the interior ones. Note that the interior and exterior angles are forming straight lines. So something plus 84 equals 180 degrees.
180-84=96
180-120=60
The sum of three angles of a triangle is 180 degrees. X is an angle. So we can form an equation to represent this. Then just solve for x!
96+60+x=180
156+x=180
x=24