Answer:-21
Step-by-step explanation:
23+22=45
45-24=21
then flip 24 and 45 to get negative
Answer:
15x - 4y =-50 -----(i)
3x - 2y=-16 --------(ii)
Using Substitution
From (i)
15x=4y-50
x=4y-50/15
Substitute x=4y-50/[15] into eqn (ii)
3x - 2y= -16
3[4y-50]/15 - 2y =-16
Multiply through by 15 to clear the fraction
3(4y - 50) - 30y=-240
12y - 150 -30y=-240
12y-30y=-240+150
-18y = -90
y=90/18
y=5.
Substitute into any eqn of choice to get x
3x - 2y=-16
3x - 2(5)=-16
3x - 10=-16
3x=-16+10
3x=-6
x=-6/3
x=-2.
x= -2
y=5
Slope = (y2 - y1)/(x2 - x1) = (-1 - 17)/(-8 - (-10)) = -18/(-8 + 10) = -18/2 = -9
I will give you everything I can do:
11)
Lets say Car A travels at x mph. That means Car B travels at x+2 mph.
Both of them are traveling towards each others, so we can say the total speed is 2x+2.
Now i takes 3 hrs and we know the distance.
Since R*T=D
Then 3(2x+2)=270
So 2x+2=90
2x=88
x=44
12)
To find perpendicular we want to find the opposite reciprocal of the original slope. Therefore the slope is 3/2.
Now we must find the equation of the line with the given variable.
First find b.
5=3/2*4+b
b = -1
So the equation of this line is:
y=3/2x-1
13) All work will be shown below.
6-3(-2-4x)=2(3(x-4)+7)
6+6+12x=2(3x-12+7)
12+12x=2(3x-5)
12+12x=6x-10
6x=-2
x = -1/3
14)
First we must find the amount each train traveled.
The speed of F train(Freight train)=x
The speed of P train(passenger train)=x+6
Their combined speed is 2x+6
It takes 2 hrs to cover 100 miles
So 2(2x+6)=100
2x+6=50
2x=44
x=22
So the freight train covered 44 miles and the passenger train covered 56 miles.
To find average speed you must do Total Distance/Total Time.
44/2 and 56/2
Which are 22 and 28.
The average speed of F train is 22 mph and average speed of P train is 28 mph.
15) Again opposite reciprocal.
3/5 -> -5/3
Work:
-4=-3*-5/3+b
-4=5+b
b=-9
y = -5/3x-9
16)
F=kx-kx0
First kx0 = 0
So F=kx
So x=F/k
