Answer:
a rectangle is twice as long as it is wide . if both its dimensions are increased 4 m , its area is increaed by 88 m squared make a sketch and find its original dimensions of the original rectangle
Step-by-step explanation:
Let l = the original length of the original rectangle
Let w = the original width of the original rectangle
From the description of the problem, we can construct the following two equations
l=2*w (Equation #1)
(l+4)*(w+4)=l*w+88 (Equation #2)
Substitute equation #1 into equation #2
(2w+4)*(w+4)=(2w*w)+88
2w^2+4w+8w+16=2w^2+88
collect like terms on the same side of the equation
2w^2+2w^2 +12w+16-88=0
4w^2+12w-72=0
Since 4 is afactor of each term, divide both sides of the equation by 4
w^2+3w-18=0
The quadratic equation can be factored into (w+6)*(w-3)=0
Therefore w=-6 or w=3
w=-6 can be rejected because the length of a rectangle can't be negative so
w=3 and from equation #1 l=2*w=2*3=6
I hope that this helps. The difficult part of the problem probably was to construct equation #1 and to factor the equation after performing all of the arithmetic operations.
Answer:
y = 5x - 7
Step-by-step explanation:
Using the equation of a line with two points
y_2 - y_1 / x_2 - x_1 = y - y_1 / x - x_1
Giving two points
( -4 , 10)(16 , -2)
x_1 = -4
y_1 = 10
x_2 = 16
y_2 = -2
Using the above formula
y_2 - y_1 / x_2 - x_1 = y - y_1 / x - x_1
-12 - 3 / -1 - 2 = y - 3 / x - 2
-15/-3 = y - 3 /x - 2
Cross multiply
-15(x - 2) = -3(y - 3)
-15x + 30 = -3y + 9
-15x + 30 + 3y - 9 = 0
-15x +30 - 9 + 3y = 0
-15x + 21 + 3y = 0
3y = 15x - 21 ( following y = mx + C
Dividing through by 3 to find y
3y/3 = 15x -21 / 3
y = 15x - 21 / 3
We can still separate
y = 15x / 3 - 21/3
y = 5x - 7
Therefore, the equation of the line is
y = 5x - 7
4.85 is the answer because if you subtract 51.2 from 56.05 you get your answer
Answer:
16 minutes
Step-by-step explanation:
If it takes Jada 20 minutes and it takes Andre 80% as long, then you multiply 20 by %80
20 * .80 = 16 minutes
