3x + y = 3
7x + 2y = 1
First isolate one of the variables (x or y) in one of the equations.
Isolate "y" in the first equation(because it is the easiest to isolate) and substitute it into the second equation.
3x + y = 3 Subtract 3x on both sides
3x - 3x + y = 3 - 3x
y = 3 - 3x
7x + 2y = 1
7x + 2(3 - 3x) = 1 [since y = 3 - 3x, you can substitute (3-3x) for "y"]
Multiply/distribute 2 into (3 - 3x)
7x + (3(2) - 3x(2)) = 1
7x + 6 - 6x = 1
x + 6 = 1 Subtract 6 on both sides
x = -5
Now that you know "x", substitute it into one of the equations (I will do both)
3x + y = 3
3(-5) + y = 3 [since x = -5, you can plug in -5 for "x"]
-15 + y = 3 Add 15 on both sides
y = 18
7x + 2y = 1
7(-5) + 2y = 1
-35 + 2y = 1 Add 35 on both sides
2y = 36 Divide 2 on both sides
y = 18
x = -5, y = 18 or (-5, 18)
2 - 2 x 3 + 3
= 2 - 6 + 3
= -4 + 3
= -1
Answer:
When you fill in the blanks you get ($0.25*x)+(0.1*y)+(0.05*z). When you evaluate it you get $1.35, which is the total amount of change in her pocket.
Step-by-step explanation:
All of the numbers that are given in the equation are values of the coins (ex: a quarter is worth $0.25) and the variables are the different coins. Multiply the quantity of each coin (that's the variable) by its value then add them together. Finally, plug in the numbers it gives you for x, y, and z.
Answer:
Step-by-step explanation:
2600(1+0.043/12)^6(1+0.137/12)^7
C. 8^4x
64^2x = 4096x
8^4x= 4096x