5x+5=6.4-2.7x
7.7x=1.4
x=1.4/7.7
x=0.181818...
0.2(6x+1)=0.5x
1.2x+0.2=0.5x
0.7x=-0.2
x=-0.2/0.7
x=-0.285714285714......
Let's solve this by substitution.
y is given by the 2nd eqn as y = (1/3)x + 7. Subst. (1/3)x + 7 into the first eqn as a replacement for y: x + 9( (1/3)x + 7) = 3.
clear out fractions by mult. all 3 terms by 3: 3x + 9x + 63 = 3
Combine like terms: 12x = -60. Then x = -5
Find y by subst. -5 for x in the 2nd equation: y = (1/3)(-5) + 7
= -5/3 + 35/3 = 30/3 = 10.
Thus, the solution (x,y) of this system is (-5,10).
Y= x + 3
1. Find the gradient(slope)
1 - 7 / - 2 - 4
=1
2. Find the y. Intercept ( c )
Y = x + c
Replace by any of the two coordinates given (4 , 7 )
7 = 4 + c
C= 3
Equation => Y = x + 3
Answer:
25 mm
Step-by-step explanation:
Set up a proportion where x is the number of millimeters for 160 kilometers
= 
Cross multiply and solve for x:
32x = 800
x = 25
So, 25 millimeters represent 160 kilometers
Answer:
7/20
Step-by-step explanation:
Seventh grade: Total = 3 + 7 = 10
Number of boys = 7 boys
Probability of a boy being picked = 7/10
Eighth grade: Total 5 + 5 = 10
Number of boys = 5
Probability 5/10 = 1/2
The probability of the correct outcome = 7/10 * 1/2 = 7 / 20
Answer: 7 / 20
