Answer:
13
Step-by-step explanation:
Set Susan's present age as x, her age from 3 years ago as x-3, and her age in three years as 2(x-3)
Since her age in seven years = 2 times as old as she way 3 years ago, set up the equation:
x+7 = 2(x-3)
x+7 = 2x-6
x = 13
Answer:
2
Step-by-step explanation:
1+1=2
A) 5000 m²
b) A(x) = x(200 -2x)
c) 0 < x < 100
Step-by-step explanation:
b) The remaining fence, after the two sides of length x are fenced, is 200-2x. That is the length of the side parallel to the building. The product of the lengths parallel and perpendicular to the building is the area of the playground:
A(x) = x(200 -2x)
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a) A(50) = 50(200 -2·50) = 50·100 = 5000 . . . . m²
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c) The equation makes no sense if either length (x or 200-2x) is negative, so a reasonable domain is (0, 100). For x=0 or x=100, the playground area is zero, so we're not concerned with those cases, either. Those endpoints could be included in the domain if you like.
Answer: See explanation.
Step-by-step explanation:
Let's assume that you have a System of two equations. You can solve this System using the Substitution Method.
In order to use that method to solve the System of equations, you can follow the steps shown below:
Step 1: You must choose one of the equations of the system and solve for one of the variables. Let's call this new equation "Equation A"
Step 2: Then you must substitute"Equation A" into the other equation.
Step 3: Now you must solve for the other variable in order to find its value.
Step 4: Finally, you need to substitute the value of the variable obtained in the previous step, into the "Equation A" and then evaluate in order to find the value of the other varibale.
(Note: You can also substitute the value of the variable calculated in Step 3 into any original equation and solve for the other variable to find its value).
Answer:
B
Step-by-step explanation:
The equation of a line in slope- intercept form is
y = mx + c (m is the slope and c the y- intercept )
Calculate m using the slope formula
m = (y₂ - y₁ ) / (x₂ - x₁ )
with (x₁, y₁ ) = (0, 6) and (x₂, y₂ ) = (6, 0)
m = 
= 
= - 1
Note the line crosses the y- axis at (0, 6 ) ⇒ c = 6
y = - x + 6 or y = 6 - x ⇒ B
