Degree is 3 and total of two terms.
"31-inch piece of steel is cut into three pieces"
Call the pieces a,b,c
a + b + c = 31
"second piece is twice as long as the first piece"
b = 2a
"third piece is one inch more than seven times the length of the first piece"
c = 1 + 7a
Ok, we have our equations, let's substitute the second and third into the first.
a + 2a + 1 + 7a = 31
10a + 1 = 31
10a = 30
a = 30/10 = 3
b = 2a = 6
c = 1 + 7a = 22
Check: 3 + 6 + 22 = 31, good
Answer: 3 inches, 6 inches, 22 inches
It's C first find 3/5 of the horoziotal
Answer:
0.5
Step-by-step explanation:
Let D be the event of selecting a marble with dots.
Let P be the event of selecting a purple marble.
The probability of selecting a marble with dots, P(D)=0.2
The probability of selecting a marble that is both purple and has dots, 
We want to determine the probability of selecting a purple marble given that the marble has dots on it, P(P|D)
By the definition of conditional probability:

The probability of selecting a purple marble given that the marble has dots on it is 0.5.
1. 78 = 0.15x
78 / 0.15 = x
520 = x.....so 78 is 15% of 520
2. | 3x - 2 | = 8 | x + 1 | = 1
3x - 2 = 8 -(3x - 2) = 8 x + 1 = 1 -(x + 1) = 1
3x = 8 + 2 -3x + 2 = 8 x = 1 - 1 -x - 1 = 1
3x = 10 -3x = 6 x = 0 -x = 2
x = 10/3 x = -2 x = -2
ur answer is : x = -2
3. 3y - 4x + 5 = 0
3y = 4x - 5
y = 4/3x - 5/3
slope = 4/3