All categories

3 years ago

Can someone help me with 2 math problems?

Mathematics

2 answers:

aleksandrvk [35]3 years ago

8 0

Yes, how can I help you

Evgen [1.6K]3 years ago

4 0

Yes how can I help ask your question

You might be interested in

Barbara drives between Miami, Florida, and West Palm Beach, Florida. She drives 50 mi in clear weather and then encounters a thu

cluponka [151]

Answer:

Her speed driving in nice weather is 50 mph and in thunderstorm is 32 mph.

Step-by-step explanation:

Barbara drives 50 miles in clear weather and then encounters a thunderstorm for the last 16 miles.

Suppose, her speed in nice weather is $x$ mph.

As she drives 18 mph slower through the thunderstorm than she does in clear weather, so her speed in thunderstorm will be: $(x-18) mph$

We know that, $Time = \frac{Distance}{Speed}$

So, the time of driving in clear weather $=\frac{50}{x}$ hours

and the time of driving in thunderstorm $=\frac{16}{x-18}$ hours.

Given that, the total time for the trip is 1.5 hours. So, the equation will be......

$\frac{50}{x}+ \frac{16}{x-18}=1.5 \\ \\ \frac{50x-900+16x}{x(x-18)}=1.5\\ \\ \frac{66x-900}{x(x-18)}=1.5 \\ \\ 1.5x(x-18)=66x-900\\ \\ 1.5x^2-27x=66x-900\\ \\ 1.5x^2-93x+900=0\\ \\ 1.5(x^2 -62x+600)=0\\ \\ x^2 -62x+600=0\\ \\ (x-50)(x-12)=0$

Using zero-product property.........

$x-50=0\\ x=50\\ \\ and\\ \\ x-12=0\\ x=12$

We need to ignore $x=12$ here, otherwise the speed in thunderstorm will become negative.

So, her speed driving in nice weather is 50 mph and her speed driving in thunderstorm is (50-18) = 32 mph

3 0

3 years ago

3. In the figure below, E is on AD and C is on BD. The dimensions given are in meters. What is the length, in meters, of CD?

damaskus [11]

Answer:

C. 3,960

Step-by-step explanation:

∆ADB ~ ∆EDC. Therefore,

$\frac{AB}{EC} = \frac{DB}{DC}$

$\frac{2,000}{1,200} = \frac{2,640 + x}{x}$ (substitution)

Solve for x

$\frac{5}{3} = \frac{2,640 + x}{x}$

Cross multiply

$5*x = 3(2,640 + x)$

$5x = 7,920 + 3x$

5x - 3x = 7,920

2x = 7,920

x = 7,920/2

x = 3,960 meters

7 0

2 years ago

which operation must you use to calculate the submarine's change in elevation? which word or words in the problem signify this o

Natasha_Volkova [10]

The order of operations

3 0

3 years ago

Read 2 more answers

Write an expression based on description; use grouping symbols

Harman [31]

Answer:

it's your answer and make me barinly least

8 0

3 years ago

4/5,9/10,17/20 least to greatest

Lana71 [14]

Answer: 4/5 17/20 9/10

Step-by-step explanation:

Find a common denominator

4/5-16/20

17/20-17/20

9/10-18/20

6 0

3 years ago

Read 2 more answers