21
18=0.86x - 0.09 Put 18 as the y value and solve for x
18.09=0.86x Add 0.09 on both sides.
21.03=x Then divide on both sides by 086
Answer:
The value of c that completes the square
is 1
Step-by-step explanation:
We need to find the value of c that completes the square 
The formula used will be: 
In the question given the value c can be found by breaking the middle term. we are given 2x while the general formula is 2ab for middle term so,
2(x)(1) = 2x
so, c= 1
Solving:

So, the value of c that completes the square
is 1
The answer is 6/5 (six over five) 100 divided by 20
15)
20/8 = x / 6
x = 20 * 6 / 8
x = 15
16)
18/54 = (x+4)/75
1/3 = (x+4) / 75
3(x+4) = 75
3x + 12 = 75
3x = 63
x = 21
SF = 54/18
SF = 3
17)
complement angles sum = 90
90 /18 = 5
so
5 x 11 = 55
5 x 7 = 35
smaller angle = 35 degrees
18)
ratio 4:5:9
4+5+9 = 18
sum of interior angles of a triangle = 180
180 / 18 = 10
largest angle = 10 x 9 = 90
answer
largest angle = 90 degrees
Answer:
Yes. It is a rational number.