Answer:
1/sqrt10
Step-by-step explanation:
1) Find out cosA using formula (cosA)^2+(sinA)^2=1
The module of cosA= sqrt (1- (-3/5)^2)= sqrt 16/25=4/5
So cosA=-4/5 or cosA=4/5.
Due to the condition 270degrees< A<360 degrees, 0<cosA<1 that's why cosA=4/5.
2) Find sinA/2 using a formula cosA= 1-2sinA/2*sinA/2 where cosA=4/5.
(sinA/2)^2= 0.1
sinA= sqrt 0.1= 1/ sqrt10 or sinA= - sqrt 0.1= -1/sqrt10
But 270°< A< 360°, then 270/2°<A/2<360/2°
135°<A/2<180°, so sinA/2 must be positive and the only correct answer is
sin A/2= 1/sqrt10
Answer:
She made 12 two point basket.
Step-by-step explanation:
Assuming the number of 2 point basket is x and that of 3 point basket is y.
Based on the question the total numbers of basket is 14, that is x + y = 14 , and the total numbers of points is 30, which helps us with our second equation 2(x) +3(y)=30.
x + y = 14 eqn 1
2(x) +3(y)=30 eqn 2
Using elimination method multiplying eqn 1 by -3 and adding it to equation 2
-3x-3 y = -42 adding to eqn 2 gives
-x= -12
x=12. Which gives the number of the 2 points basket she made .
Answer:
I'm confused what is the question?
Step-by-step explanation:
Mr. Reed DATA:
rate = 40 mph ; time = x 4.5 hrs ; distance = 40x miles
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Mrs. Reed DATA:
rate = 60 mph ; time = x hrs ; distance = 60x - 210 miles
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Equation:
40x = 60x -210
-20x = -210
x = 10.5 hrs
x-3.5 = 7 hrs (Mr. Reed's time)
Answer:
180
Step-by-step explanation:
There are 60 minutes in one hour. Multiply 3 x 60 = 180.
