Answer:
60cm^2
Step-by-step explanation:
use Pythagoras' theorem to find the height (attached)
24/2 = 12
h=5cm
are of a triangle = base x height /2
24 x 5 / 2 = 120/2 = 60
if there is 4 digits and 9 numbers each there is a possibility of 9 to the power of 4 different combinations.
Part (i)
I'll use H in place of T to represent the heat of the object. That way there isn't a clash of variables lowercase t vs uppercase T.
The equation we're working with is updated to:
H(t) = 22 + a*2^(bt)
Plugging in t = 0 as the initial time value should lead to the temperature being H = 86 degrees Celsius.
So,
H(t) = 22 + a*2^(bt)
86 = 22 + a*2^(b*0)
86 = 22 + a*2^0
86 = 22 + a*1
86 = 22 + a
a+22 = 86
a = 86-22
a = 64
<h3>Answer: 64</h3>
=====================================================
Part (ii)
We'll use the value of 'a' we found earlier. Plus we'll use the fact that H = 28 when t = 0.5 (since 30 min = 30/60 = 0.5 hr).
H(t) = 22 + a*2^(bt)
28 = 22 + 64*2^(b*0.5)
28-22 = 64*2^(0.5b)
64*2^(0.5b) = 6
2^6*2^(0.5b) = 6
2^(6+0.5b) = 6
log( 2^(6+0.5b) ) = log(6)
(6+0.5b)*log(2) = log(6)
6+0.5b = log(6)/log(2)
6+0.5b = 2.5849625
0.5b = 2.5849625-6
0.5b = -3.4150375
b = -3.4150375/(0.5)
b = -6.830075
<h3>Answer: Approximately -6.830075</h3>
Answer:
Step-by-step explanation:
The end point of a ray is named first. The name of another point on the ray completes the ray name. Any arrow over the name will be single ended, with its tail over the name of the endpoint.
A ray with endpoint B will be B[something] with an over-arrow pointing to the right:
Answer:
Step-by-step explanation:
events A and B are independent:
P(A and B) = P(A)×P(B)
9/100= P(A)×9/20
P(A) = (9/100)/(9/20)
P(A) = (9/100) ×(20/9) =180/900
P(A) = 0.2