Answer:
(3, 3 )
Step-by-step explanation:
Given the 2 equations
3x - y = 6 → (1)
6x + y = 21 → (2)
Adding the 2 equations term by term will eliminate y, that is
(6x + 3x) + (y - y) = (21 + 6), that is
9x = 27 (divide both sides by 9 )
x = 3
Substitute x = 3 into either (1) or (2) and solve for y
Using (2), then
(6 × 3) + y = 21
18 + y = 21 ( subtract 18 from both sides )
y = 3
Solution is (3, 3 )
Answer:
Ron has 15 nickels and 9 quarters
Step-by-step explanation:
Create a system of equations where n is the number of nickels and q is the number of quarters he has:
n + q = 24
0.05n + 0.25q = 3
Solve by elimination by multiplying the top equation by -0.25
-0.25n - 0.25q = -6
0.05n + 0.25q = 3
Add them together and solve for n:
-0.2n = -3
n = 15
So, Ron has 15 nickels. Find how many quarters he has by subtracting 15 from 24:
24 - 15
= 9
So, Ron has 15 nickels and 9 quarters.
Answer:
Step-by-step explanation:
Jada is making circular invitations
we have d=12 cm, the radius r=6
she needs to find out the circumference
C=2x3.14x r
C=2x 3.14x6=37.68
180/37.68=4.77
she can make just 4 invitations
