Help me solve thsibproblem

A car travels for 4(t+3) hours at a constant speed of 10(t+3) km/h. If the total distance travelled by the car is 810 km, find t

IceJOKER [234]

Step-by-step explanation:

$\because \: time \times speed = distance \\ \therefore \: 4(t + 3) \times 10(t + 3) = 810 \\ \therefore \: 4(t + 3)^{2} = 81 \\ \therefore \: \{2(t + 3) \}^{2} = {9}^{2} \\ \therefore \: \{2(t + 3) \} = {9} \\ \therefore \: t + 3 = \frac{9}{2} \\ \therefore \: t = \frac{9}{2} - 3 \\ \therefore \: t = \frac{9 - 6}{2} \\ \therefore \: t = \frac{3}{2} \\ \therefore \: t = 1.5 \: hrs \\$

$\because \: time \times speed = distance \\ \therefore \: 4(t + 3) \times 10(t + 3) = 810 \\ \therefore \: 4(t + 3)^{2} = 81 \\ \therefore \: \{2(t + 3) \}^{2} = {9}^{2} \\ \therefore \: \{2(t + 3) \} = {9} \\ \therefore \: t + 3 = \frac{9}{2} \\ \therefore \: t = \frac{9}{2} - 3 \\ \therefore \: t = \frac{9 - 6}{2} \\ \therefore \: t = \frac{3}{2} \\ \therefore \: t = 1.5 \: hrs \\ speed \: of \: car = 10(t + 3) \\ \hspace{60 pt} = 10(1.5 + 3) \\ \hspace{60 pt}= 10 \times 4.5 \\ \red{ \boxed{ \bold{ \therefore \: speed \: of \: car = 45 \:km/ h}}} \\$

3 0

4 years ago

A penny falls from the top of Hard Rock Stadium The height of the penny after a seconds is given by f(x) = 350 - 16x²

7nadin3 [17]

Answer:

B C E

Step-by-step explanation:

Read the question

3 0

3 years ago

Just 6, 8, and 10 plz<br> thx

marshall27 [118]

6 - 15/40 = 0.375 = 37.5%
When looking to convert a decimal to a percent you move the decimal over two places so, 0.375 becomes 37.5

8 - 70*1.2 = 80

You see 100% is equal to 1.00 when multiplying/dividing. So 1.2 = 120%

10 - 48*0.25 = 12 and 12+48 = 60 So, 60.

Here, we use 0.25 because 100% - 75% = 25% or... 1.0 - 0.75 = 0.25

7 0

4 years ago

The Trapezoidal rule Tn on the interval [0,5) will be exact for

igomit [66]

Answer:

degree 1

Step-by-step explanation:

The trapezoidal rule is exact when the second derivative is zero. This occurs when the polynomial is degree one or less

5 0

3 years ago

3 On a coordinate grid, the location of a lighthouse is at L, and the location of a buoy is at B. At noon, a ship is at the midp

Zarrin [17]

Answer:

$(\frac{1}{2}, 2)$

Step-by-step explanation:

Using the midpoint formula, $M(\frac{x_1 + x_2}{2}, \frac{y_1 + y_2}{2})$ , we can find the coordinates that represents the position of the ship at noon.