Answer:
x = 3
y = 0
Step-by-step explanation:
The method of substitution is when one solves an equation for one of the variables, and then substitutes the expression into the other equation. After doing so, one will solve the other equation for the remaining variable and then backsolve for the first variable.
4x + 2y = 12
x = y + 3
The second equation is already sovled for parameter (x), subttiute this into the other equation,
4(y + 3) + 2y = 12
Distribute,
4y + 12 + 2y = 12
Simplify,
6y + 12 = 12
Inverse operations,
6y + 12 = 12
-12
6y = 0
/6
y = 0
Backsolve for (x), substitute the value of (y) into the equation for (x) and solve,
x = y + 3
x = 0 + 3
x = 3
11. Assuming distance is proportional to time,
.. (3 h)/(7 h) = d/(665 km)
.. d = (665 km)*(3/7) = 285 km . . . . . . selection B
12. (30 L)/(1.5 L/min) = 20 min . . . . . . selection C
F(x+1) = (x + 1)^3
= 3x + 3
= 3(0) + 3
= 3
I think is 3
Answer:
(6,-4)
Step-by-step explanation:
-3x-9y = 18 (equation 1)
4x+3y = 12 (equation 2)
multiply equation 2 by 3, and add it to equation 2
-3x-9y = 18
12x+9y = 36
-----------------
X's cancel out
9x = 54
Divide both sides by 9
x = 6
Plug in 6 for x in any of the original equations
(Plugging into Equation 2)
4(6)+3y = 12 Multiply 4(6)
24+3y = 12 Subtract 24 from both sides
3y = -12 Divide 3 on both sides
y = -4
Therefore the solution is (6,-4).
Answer:
Step-by-step explanation:
4x-8y