A trough has ends shaped like isosceles triangles, with width 2 m and height 5 m, and the trough is 18 m long. Water is being pu
1 answer:
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Answer:
The length of the rectangle is 9 cm
Step-by-step explanation:
Given: The length of rectangle(l) = (x+3) cm and a width of rectangle (w) = cm a
Also, perimeter of rectangle is 24 cm.
Perimeter of rectangle is to add the lengths of all the four sides.
Perimeter of rectangle (P) is given by;
P=2(l+w)
Substituting the value of P = 24 cm , l = (x+3) cm and w =
then,
Divide by 2 both sides of an equation;
Combine like terms;
Subtract 3 from both the sides we get;
Simplify:
Multiply both sides by we get
Therefore, length of rectangle(l) = (x+3) = 6+3 = 9 cm
Answer: Choice B
(-2, 5)
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Explanation:
The original system is
Multiply both sides of the second equation by 3. Doing so leads to this updated system of equations
Now add straight down
The x terms add to -4x+3x = -1x = -x
The y terms add to 3y+(-3y) = 0y = 0
The terms on the right hand sides add to 23+(-21) = 2
We end up with the equation -x = 2 which solves to x = -2
Now use this to find y. You can pick any equation with x,y in it
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-4x+3y = 23
-4(-2)+3y = 23
8+3y = 23
3y = 23-8
3y = 15
y = 15/3
y = 5
Or
x-y = -7
-2-y = -7
-y = -7+2
y = -5
y = 5
Either way, we get the same y value.
So that's why the solution is (x,y) = (-2, 5)