by pythagorean formula, the last side is √(61)
by cos rule
cos A

A = 39.81
Answer:
-
Step-by-step explanation:
A root with square root or under root is only obtained when we take the square root of both sides. Remember that when we take a square root, there are two possible answers:
- One answer with positive square root
- One answer with negative square root
For example, for the equation:

If we take the square root of both sides, the answers will be:

Only getting one solution with square root is not possible. Solutions with square root always occur in pairs.
For given case, the roots are 6 and
. Therefore, the 3rd root of the polynomial function f(x) had to be -
It seems you made error while writing option B, it should be - square root of 5.
1)
I:x-y=-7
II:x+y=7
add both equations together to eliminate y:
x-y+(x+y)=-7+7
2x=0
x=0
insert x=0 into II:
0+y=7
y=7
the solution is (0,7)
2)
I: 3x+y=4
II: 2x+y=5
add I+(-1*II) together to eliminate y:
3x+y+(-2x-y)=4+(-5)
x=-1
insert x=-1 into I:
3*-1+y=4
y=7
the solution is (-1,7)
3)
I: 2e-3f=-9
II: e+3f=18
add both equations together to eliminate f:
2e-3f+(e+3f)=-9+18
3e=9
e=3
insert e=3 into I:
2*3-3f=-9
-3f=-9-6
-3f=-15
3f=15
f=5
the solution is (3,5)
4)
I: 3d-e=7
II: d+e=5
add both equations together to eliminate e:
3d-e+(d+e)=7+5
4d=12
d=3
insert d=3 into II:
3+e=5
e=2
the solution is (3,2)
5)
I: 8x+y=14
II: 3x+y=4
add I+(-1*II) together to eliminate y
8x+y+(-3x-y)=14-4
5x=10
x=2
insert x=2 into II:
3*2+y=4
y=4-6
y=-2
the solution is (2,-2)
Answer: Any amount of milage more than 30
Step-by-step explanation: You can write an equation to compare the relationship between the costs that looks like:
102<75+0.9m
27=0.9m
m=30