Solving Systems by Elimination 3a

Find the area of a circle with radius of 7

zubka84 [21]

Answer:

-The area of a circle:

$A \approx 153.938$

or

$A \approx 153.94$ (Rounded to nearest hundredth if needed)

Step-by-step explanation:

-Use the formula to find the area of a circle:

$A = \pi r^2$

-After you have the formula set up, use the radius for the formula:

$A = \pi 7^2$

-Then, you solve the formula:

$A = \pi \times 7^2$

$A = \pi \times 49$

$A = 49\pi \approx 153.938$

-Round up to the nearest hundredth (if needed):

$A \approx 153.94$

4 0

3 years ago

4. BAKE SALE Ashley has $15 in the Pep

Mekhanik [1.2K]

Answer:

a) 187.5 b) Domain c ∈ [0,187.5] c) Range ∈ [0,15]

Step-by-step explanation:

a) In this function, d stands for dollars and c stands for cookies. Ashley left $15 to pay supplies for making new cookies. The more cookies they made the less money it is left. For instance, If someone bakes 1 cookie using that money:

d=15-0.08c d=15-0.08(1) d=14.92 Then $14.92 is left after baking 1 cookie. And so on.

To find the zero of this function, let's turn this into an equation.

$d=15-0.08c\\0=15-0.08c\\-15=-0.08c\\\ \frac{0.08}{0.08}c=\frac{15}{0.08}\\c=187.5$

So according to this function, with 15 dollars at least 187 cookies can be made.

b) The function d=15-0.08c if it was defined for the Real Set, any value would be valid within the Real Set. But c, is for cookies. Then the set is

$Z_{+}$

$d=15-0.08c\\0=15-0.08c\\-15=-0.08c\\\ \frac{0.08}{0.08}c=\frac{15}{0.08}\\c=187.5$

Domain c ∈ [0,187.5]

c) The Range

The Range is the subset of all values between $15 and 0$, since after the money is over they can no longer bake cookies. And there's $-1 dollar note.

So the Range is d ∈ [0,15]

8 0

3 years ago

Consider all angles whose reference angle is 45° with terminal sides not in Quadrant I.The angles that share the same cosine val

Oksana_A [137]

Solution:

As we know reference angle is smallest angle between terminal side and X axis.

As cosine 45 ° is always positive in first and fourth quadrant.

i.e CosФ, Cos (-Ф) or Cos(2π - Ф) have same value.

As, Cos 45°, Cos (-45°) or Cos ( 360° - 45°)= Cos 315°are same.

So, Angles that share the same Cosine value as Cos 45° have same terminal sides will be in Quadrant IV having value Either Cos (-45°) or Cos (315°).

Also, Cos 45° = Sin 45° or Sin 135° i.e terminal side in first Quadrant or second Quadrant.