Answer:
(a) (5, -3)
Step-by-step explanation:
The "substitution method" for solving a system of equations requires that you write an expression that can be substituted for a variable in one or more of the other equations in the system.
<h3>Expression to substitute</h3>
The given equations are ...
We notice the first equation gives an expression for y. This is exactly what we want to substitute for y in the second equation.
<h3>Substitution</h3>
When the expression (x-8) is substituted for y in the second equation, you get ...
2x +3(x -8) = 1
This simplifies to ...
5x -24 = 1
<h3>Solution</h3>
This 2-step equation can now be solved in the usual way:
5x = 25 . . . . . . add 24 to isolate the variable term
x = 25/5 = 5 . . . . . divide by the coefficient of x
Note that we now know what the correct answer choice is.
Using the expression for y, we find ...
y = x -8 = 5 -8 = -3
The solution is (x, y) = (5, -3).
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The attached graph confirms this solution.
1 week = 7 days
1 gallon = 16 cups ⇒ 1 cup = 1/16 gallon
1.5 cups = 1.5 · 1/16 gallon = 15 · 1/160 gallon = 3/32 gallon
1.5 cups per day = 3/32 gallons per day = 7 · 3/32 gallons per week
= 21/32 gallons per week
I believe that triangle B and E are right triangles.
Answer:
n = -12
Step-by-step explanation:
(-2/3)n + 7 = 15
(-2/3)n+7-7 = 15-7 Subtract by 7 on both sides
(-2/3)n = 8 Multiply by the reciprocal of the fraction, which is
(-2/3)n*(-3/2) = 8(-3/2) This makes it so you get n *1 and isolates n.
n = -24/2 = -12