Is it multiple choice? If so, leave the answer choices.
So first one
'how many solutions does 2x-y=-5 and 2x+y=5 have?'
add and get
2x-y-5
plus
2x+y=5
equals
2x+2x+y-y=5-5
4x=0
x=0 always
solve for y
4(0)+y=5
y=5
the solution is (0,5)
only <u>ONE </u>solution
one way is to subsitute
just remember that it is in (x,y) form so
the pont (1,2) means that 1 solution is x=1 and y=2 so subsitute and find that
the first one is the answer you are correct
just look at the graph
the solution is the intersection
it seems to be at a point that is 3 units to the right and -6 units up (6 units down)
so the solution is (3,-6)
yo are corect
subsitution
y=y
therefor
the answe ris (-4,-14) if you did the math correctly
#8 is correct
# 9 is correct
# 10 the answe ris bananas=0.40 pears=0.60
the last one you got it wrong, remember to check your answer to the graph for commonsense
then answer is (-2,5) and (1,2)
For the complex roots I got 1,2,-3
Find cos using trig identities:
Therefore
Sub in tan x = 3, (Note that x is in 3rd quadrant, cos x < 0)
Finally, sub into Half-angle formula:(Note x/2 is in 2nd quadrant, tan x<0)
