First picture)
I: 5x+2y=-4
II: -3x+2y=12
add I+(-1*II):
5x+2y-(-3x+2y)=-4-12
8x=-16
x=-2
insert x=-2 into I:
5*(-2)+2y=-4
-10+2y=-4
2y=6
y=3
(-2,3)
question 6)
I: totalcost=115=3*childs+5*adults
II: 33=adults+childs
33-adults=childs
insert childs into I:
115=3*(33-adults)+5*adults
115=99-3*adults+5*adults
16=2*adults
8=adults
insert adults into II:
33-8=childs
25=childs
so it's the last option
question 7)
a) y<6 and y>2 can also be written as 2<y<6, so solution 3 exist for example
b) y>6 and y>2 can also be written as 2<6<y, so solution 7 exist for example
c) y<6 and y<2 inverse of b: y<2<6, so for example 1
d) y>6 and y<2: y<2<6<y, this is impossible as y can be only either bigger or smaller than 2 or 6
so it's the last option
question 8)
I: x+y=12
II: x-y=6
subtract: I-II:
x+y-(x-y)=12-6
2y=6
y=3
insert y into I:
x+3=12
x=9
(9,3)
question 9)
I: x+y=6
II: x=y+5
if you take the x=y+5 definition of II and substitute it into I:
(y+5)+y=6
which is the second option :)
Answer: 1/6 is not equal to 6/12 because 6/12 is 1/2 and 1/6 is less
Step-by-step explanation:
Well if the student already finished 6 problems out of 15, there are 15-6 = 9 homework questions she still has to finish.
Still needs to complete: 9.
Already finished: 6
9 : 6.
Simplified: 3 : 2
Answer: y = 2x+22
========================================================
Explanation:
The equation y = 2x+5 is in the form y = mx+b
m = 2 = slope
b = 5 = y intercept
Parallel lines have equal slopes, but different y intercepts. So the answer will be in the form y = 2x+c, where b and c are different numbers. Since b = 5, this means c must be some other number. If c = 5, then we'd have the exact same line.
Let's plug in (x,y) = (-5,12), along with the slope m = 2, and solve for c
y = mx+c
12 = 2(-5)+c
12 = -10+c
12+10 = c
22 = c
c = 22
Since m = 2 and c = 22, we go from y = mx+c to y = 2x+22
The equation of the parallel line is y = 2x+22
The graph is below.
You add/subtract complex numbers simply by adding/subtracting real parts and imaginary parts.
So, the real part of this sum is the sum of the real parts:
And the imaginary part of this sum is the sum of the imaginary parts:
So, you have
