Answer:
D) 171 cm²
Step-by-step explanation:
You don’t actually need to decompose it. You could just do it as a trapezoid:
(15+23)/2=19
19x9=171
If you want to decompose it into 2 triangles and a rectangle:
10=15x9=135
1/2(3)(9)=13.5
1/2(5)(9)=22.5
135+13.5+22.5=171 also
No. The area doesn't tell you the dimensions, and you need
the dimensions if you want the perimeter.
If you know the area, you only know the <em><u>product</u></em> of the length and width,
but you don't know what either of them is.
In fact, you can draw an infinite number of <em><u>different</u></em> rectangles
that all have the <em>same</em> area but <em><u>different</u></em> perimeters.
Here. Look at this.
I tell you that a rectangle's area is 256. What is its perimeter ?
-- If the rectangle is 16 by 16, then its perimeter is 64 .
-- If the rectangle is 8 by 32, then its perimeter is 80 .
-- If the rectangle is 4 by 64, then its perimeter is 136 .
-- If the rectangle is 2 by 128, then its perimeter is 260 .
-- If the rectangle is 1 by 256, then its perimeter is 514 .
-- If the rectangle is 0.01 by 25,600 then its perimeter is 51,200.02
Answer:
150
Step-by-step explanation:
3×0=0
3×1=3
3×2=6
3×3=9
....
3×50=150
Answer:
The number of liters of 25% acid solution = x = 160 liters
The number of liters of 40% acid solution = y = 80 liters
Step-by-step explanation:
Let us represent:
The number of liters of 25% acid solution = x
The number of liters of 40% acid solution = y
Our system of Equations =
x + y = 240 liters....... Equation 1
x = 240 - y
A 25% acid solution must be added to a 40% solution to get 240 liters of 30% acid solution.
25% × x + 40% × y = 240 liters × 30%
0.25x+ 0.4y = 72...... Equation 2
We substitute 240 - y for x in Equation 2
0.25(240 - y)+ 0.4y = 72
60 - 0.25y + 0.4y = 72
Collect like terms
- 0.25y + 0.4y = 72 - 60
0.15y = 12
y = 12/0.15
y = 80 Liters
Solving for x
x = 240 - y
x = 240 liters - 80 Liters
x = 160 liters
Therefore,
The number of liters of 25% acid solution = x = 160 liters
The number of liters of 40% acid solution = y = 80 liters
