It depends on what variable you are tying to solve for first. Say you are trying to solve for x first and then y on the first problem you wrote.
In substitution you solve one of the equations for example with
6x+2y=-10
2x+2y=-10
you solve 2x+2y=-10 for x
2x+2y=-10
-2y = -2y (what you do to one side of the = you do to the other)
2x=-10-2y (to get the variable by its self you divide the # and the variable)
/2=/2 (-10/2=-5 and -2y/2= -y or -1y, they are the same either way)
x=-5-y
now you put that in your original equation that you didn't solve for:
6(-5-y)+2y=-10 solve for that
-30-6y+2y=-10 combine like terms
-30-4y=-10 get the y alone and to do this you first get the -30 away from it
+30=+30
-4y=20 divide the -4 from each side
/-4=/-4 (20/-4=-5)
y=-5
now the equation you previously solved for x can be solved for y.
x=-5-y
x=-5-(-5) a minus parenthesis negative -(- gives you a positive
-5+5=0
x=0
and now we have solved the problem. x=0 and y=-5
Answer:
27 days
Step-by-step explanation:
20 
÷ 
= 27
Answer: Probability that the proportion of students who graduated is greater than 0.743 is P = 0.4755
Step-by-step explanation:
Given that,
Probability of freshmen entering public high schools in 2006 graduated with their class in 2010, p = 0.74
Random sample of freshman, n = 81
Utilizing central limit theorem,
So,
= P( Z > 0.0616)
= 0.4755 ⇒ probability that the proportion of students who graduated is greater than 0.743.
Answer:
6
Step-by-step explanation:
Answer: Option D. 1,778
Solution:
Standard brick:
Width: w=3.625 in
Height: h=2.25 in
Length: l=7.625 in
Volumen of one standard brick: v
v=w*h*l
v=(3.625 in)*(2.25 in)*(7.625 in)
v=62.19140625 in^3
Pallet of bricks:
Side: s=4 feet
s=(4 feet)*(12 in / 1 feet)→s=48 in
Volume of a pallet of bricks: V=s^3
V=(48 in)^3
V=110,592 in^3
Number of bricks could be in a pallet: n
n=V/v
n=(110,592 in^3) / (62.19140625 in^3)
n=1,778.252119
n=1,778
