The area of a circle is A = πr², where r is the radius. That means in order to solve this we have to find the value of x, which is the diameter of the lake, and then divide it in half to get the radius. To find x we will use similar triangles and proportions. x is the height of the big triangle and 4.5 is the height of the smaller triangle; 15.3 + 7.4 is the hypotenuse of the big triangle and 7.4 is the hypotenuse of the smaller triangle. Setting up our proportion:

$\frac{x}{4.5}=\frac{15.3+7.4}{7.4}$ which simplifies a bit to

$\frac{x}{4.5}=\frac{22.7}{7.4}$ and cross multiply to solve for x:

7.4x = 102.15 so

x = 13.8 That is the diameter of the lake. Divide it in half to get 6.9, the radius. Applying the area formula for a circle:

A = (3.14)(6.9)² and

A = 3.14(47.61) so

A = 149.5 which rounds to 150, Choice C

5 0

3 years ago

A Triangle has an area of 36cm^2. The base and height are scaled by a factor of 5. What is the area of the resulting triangle?

Finger [1]

Answer:

Area of resulting triangle will be 900 $cm^2$ .

Step-by-step explanation:

When sides of any polygon if scaled by a factor of k

then area is scaled by $k^2$

According to the above statement

therefore here in the question since area of original triangle was 36 $cm^2$

and both base and height are scaled by a factor of 5.

therefore area of scaled triangle will be $5^2$ times of the original

that is 25 x 36 which gives 900 $cm^2$

So area of resulting triangle will be 900 $cm^2$

7 0

3 years ago

No irrational numbers are whole numbers. True or false and why?

Luda [366]

Hi!

Irrational numbers cannot be whole numbers. In order to be a whole number, you cannot have any decimals or fractions. Irrational numbers possess these properties.

Hopefully, this helps! =)

4 0

3 years ago

Read 2 more answers