What is the estimate of the sum of 5/12 and 7/8?

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

3 years ago

What is the slope of the equation y - 3 = -4(x - 5)?<br> O-4<br> O-3<br> O 20<br> O 23

abruzzese [7]

Answer0-4

Step-by-step explanation:

8 0

2 years ago

Help me plz help me plz ??

Oduvanchick [21]

Answer:

I just want points hahahaha

7 0

2 years ago

Read 2 more answers

Simplify (tan(θ)+cot(θ))/(sec(θ)•csc(θ)) completely

AlekseyPX

$\dfrac{\tan\theta+\cot\theta}{\sec\theta\csc\theta}=\dfrac{\dfrac{\sin\theta}{\cos\theta}+\dfrac{\cos\theta}{\sin\theta}}{\dfrac1{\cos\theta}\dfrac1{\sin\theta}}=\dfrac{\sin^2\theta+\cos^2\theta}1=1$

6 0

3 years ago

A car travels 76 km in 47 minutes.

Mumz [18]

Answer:

97km/h to 1dp

Step-by-step explanation:

47mins is 0.783 of an hour

76km/0.783 = 97.0212km/h

3 0

2 years ago