Answer:
3,6
Step-by-step explanation:
x+y=9
x-y=-3
Adding these two equations we get 2x = 6, x=3
y=6
Answer: 3 : 1
Step-by-step explanation:
We know that there are 48 kids in Elm street.
12 of them are boys, then the number of girls will be:
48 - 12 = 36
So there are 12 boys and 36 girls.
Then the ratio of girls to boys is 36:12
We can divide both numbers by the same number and we will get an equivalent ratio, if we divide by 12 in both sides, we have:
36/12 : 12/12
3 : 1
Then the ratio is 3 to 1.
Answer:
Part 1) The exact value of the arc length is 
Part 2) The approximate value of the arc length is 
Step-by-step explanation:
step 1
Find the circumference of the circle
The circumference of a circle is equal to
we have
substitute
step 2
Find the exact value of the arc length by a central angle of 150 degrees
Remember that the circumference of a circle subtends a central angle of 360 degrees
by proportion
step 3
Find the approximate value of the arc length
To find the approximate value, assume
substitute
Answer: the cost per unit of gas is $0.38
Step-by-step explanation:
Let x represent the cost per unit of electricity.
Let y represent the cost per unit of gas.
During one month, a homeowner used 600 units of electricity and 100 units of gas for a total cost of $344. It means that
600x + 100y = 344- - - - - - - - - -1
The next month, 400 units of electricity and 250 units of gas were used for a total cost of $299.
It means that
400x + 250y = 299- - - - - - - - - -1
Multiplying equation 1 by 400 and equation 2 by 600, it becomes
240000x + 40000y = 137600
240000x + 150000y = 179400
Subtracting, it becomes
- 110000y = - 41800
y = - 41800/- 110000
y = 0.38
Substituting y = 0.38 into equation 1, it becomes
600x + 100 × 0.38 = 344
600x + 38 = 344
600x = 344 - 38 = 306
x = 306/600
x = 0.51
Answer:
x-2x = -3 and x = 3
Step-by-step explanation:
Given the expression
y=x+5.... 1
y-2x=2.... 2
Substituting the first equation into the second we will have;
From 2;
y -2x = 2
x+5-2x = 2
x-2x +5 = 2
x-2x = 2-5
x-2x = -3
-x =-3
x =3
Hence the required equation is x-2x = -3 and x = 3
