In order to answer this one, it's really really really really helpful if you know what the law of cosines says. In fact it's absolutely necessary.
The law of cosines says if you know two sides of a triangle and the angle between them then you can use that information to find the length of the third side.
In the picture you know the lengths of two sides and you know the angle between them. So you can use the law of cosines to find the length of the third sidethat. That's side AC.
Answer:
The student is expected to spend <em>15.4 hours </em>doing homework
Step-by-step explanation:
The scattered plot shows there is a close correlation between the variables. A line of best fit will go through the 'center' of the points. Since we are not required to find an exact line, we'll draw it in red color as shown below
To know the equation of that line, we must take two clear points of it from the graph. We'll pick (28,4) and (4,25)
The equation of a line, given two points (a,b) and (c,d) is
Using the selected points
Simplifying and computing results, the equation is
Using that equation, we can predict how many hours the students will spend doing homework if they spend 15 hours watching TV
=15.4 hours
So the student is expected to spend 15.4 hours doing homework
Given equations are;<span>
2a + 3b = -1 ..................equation 1
3a + 5b = -2 ....................equation 2</span>
Now multiply equation 1 with (-3)
The equation will be;
-6a -9b = 3 …………………..equation 3
Now multiply equation 2 with (2)
The equation will be;
6a + 10b = -4 ……………..equation 4
Now add equation 3 and equation 4
-6a – 9b = 3
<span>6a + 10b = -4</span>
<span>------------------------------</span>
0a + b = -1
b = -1
Now put the value of b in equation 1
2a + 3(-1) = -1
2a -3 = -1
2a = -1+3
2a = 2
a=1
Thus the solution is (a,b) = (1,-1)
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</span>
Answer:
36
Step-by-step explanation:
-9*-4=36
