His model is incorrect because 20 x 7 is not 14, it is 140. If he had 140 instead of 14, he would have been correct.
I haven't done division like that in a long time, so this is what I think it will look like. I didn't add other work (multiplying 4 with #'s) but you can if you have to
Answer:
The area of a triangle is equal to its base times its height divided by 2: \begin{align*}A=\frac{bh}{2}\end{align*}. In order to find the composite area of two or more shapes, simply find the area of each shape and add them together.
Step-by-step explanation:
Answer:
A = 616 cm^2
Step-by-step explanation:
The area of a circle is given by
A = pi r^2
A = pi (14)^2
A = pi (196)
Using 3.14 as an approximation for pi
A = 3.14 *196
A =615.44
The nearest approximation is
A = 616 cm^2
The problem indicates that A represents the number of tablet computers sold in millions. So, if 65 million were sold, we must substitute A = 65 to the equation. Then, we find for t.
65 = 4.5t² +43.5t + 17
Solving for t using a calculator,
t = 1 and -10.67
Let's take the positive root. So, t=1.
That means the year would be 1 year after 2010. <em>Therefore, the answer is 2011.</em>
Fidn volume
V=hpir^2
d/2=r
1.4/2=0.7=r
height=3.5
V=3.5*3.14*0.7^2
V=5.3851
1.5 times t=5.3851
divide both sides by 1.5
t=3.59
round
t=4
4 minutes
