Choose the best answer.

Tim and Cynthia leave Cynthia's house at the same time. Tim drives north and Cynthia drives west. Tim's average speed is 10 mph

RSB [31]

Answer:

54.2 mph

Step-by-step explanation:

Since the drivers leave at the same time and travel in directions 90° from each other, their separation speed can be found using the Pythagorean theorem. Let c represent Cynthia's average speed. Then (c-10) will represent Tim's average speed. Their combined separation speed is 70 miles per hour, so we can write ...

70² = c² +(c -10)²

4900 = 2c² -20c +100 . . . . eliminate parentheses

c² -10c -2400 = 0 . . . . . . . . divide by 2; put in standard form

(c -5)² -2425 = 0 . . . . . . . . . rearrange to vertex form

c = 5 ±5√97 . . . . . . . . . . . . solve for c, simplify radical

c ≈ 54.244 ≈ 54.2 . . . . . . . use the positive solution

Cynthia's average speed was 54.2 miles per hour.

6 0

3 years ago

Logan wants to have $130,000 to pay for a surgery on his retractable forearm claws in 30 months. If he can invest money in an ac

dangina [55]

Answer: $107,836.69 or about $107,837 (to the nearest dollar)

Step-by-step explanation:

Formula to the accumulated amount received after investing principal amount (P) at rate of interest (r) compounded monthly for t months :

$A=P(1+\dfrac{r}{12})^{t}$

As per given , A = $130,000

r= 7.5% = 0.075

t= 30 months

Now,

$130000=P(1+\dfrac{0.075}{12})^{30}\\\\\Rightarrow 130000=P(1+0.00625)^{30}\\\\\Rightarrow 130000=P(1.00625)^{30}\\\\\Rightarrow 130000=P \times1.20552661036\\\\\Rightarrow\ P=\dfrac{130000}{1.2055266}=107,836.69$

Hence he need to invest $107,836.69 .

8 0

3 years ago

Jacob leaves his summer cottage and drives home. After

krok68 [10]

Answer:

A linear relationship can be written as:

y = a*x + b

Where a is the slope and b is the y-intercept.

If this line passes through the points (a, b) and (c, d) then the slope can be written as:

a = (a - c)/(b - d)

Here y will represent the distance between Jacob and his house, and the variable x represents the time that he has ben driving.

In this case, we know that after driving for 5 hours, he is 112km from home.

Then we can write this point as (5h, 112km)

We also know that after 7 hours he is 15km from home.

Then we can write this point as (7h, 15km)

Then the slope of this function will be:

a = (15km - 112km)/(7h - 5h) = -48.5 km/h

Then the equation is:

y = -(48.5 km/h)*x + b

To find the value of b, we can replace the values of one of the points, for example in the point (7h, 15km)

This means that we need to replace x by 12h, and y by 15km, then we get:

15km = -( 48.5 km/h)*7h + b

15km + ( 48.5 km/h)*7h = b = 354.5 km

then the equation will be:

y = (-48.5 km/h)*x + 354.5 km

Now we want to answer: How long had Jacob been driving when he was 209 km from home?

Then we need to only replace y by 209km, and solve for x:

209km = (-48.5 km/h)*x + 354.5 km

209km - 354.5 km = (-48.5 km/h)*x

-145.5km = (-48.5 km/h)*x

-145.5km/( -48.5 km/h) = x = 3h

So he is 209km away from his home after driving for 3 hours.

6 0

3 years ago

A group of 5 friends ate lunch at a restaurant. The bill came to $42 and the friends agreed to split it equally. Which expressio

Gnom [1K]

Answer:

c would be the right and its the best answer

3 0

2 years ago

In circle T, PTQ = RTS. What is the measure of PQ? 24° 33° 48° 66°

weqwewe [10]

Answer:

The correct option is D

66°

Step-by-step explanation:

Given that ∠PTQ ≅ ∠RTS

The measure of the arc SR = 66°

So ∠RTS = 66°

But also, ∠PTQ ≅ ∠RTS

Therefore ∠PTQ = 66°

and the measure of the arc PQ = ∠PTQ

Therefore, measure of the arc PQ is 66°.

4 0

3 years ago