Answer:
Step-by-step explanation:
7) Area = 615.75 sq. km
πr² = 615.75
3.14*r² = 615.75
r² = 615.75/3.14 = 196
r = √196
r = 14 km
8) circumference = 15.71 yards
πd = 15.71
3.14*d = 15.71
d = 15.71/3.14 = 5 yards
9)Area = 415.48 sq.inches
πr² = 415.48
3.14*r² = 415.48
r² = 415.48/3.14 = 132.31
r = √132.31
r = 11.5 inches
diameter = 11.5*2 = 23 inches
1234567891011121314151617181920
Answer:
Step-by-step explanation:
Step one:
given
cost per drive= $20
additional fee per person= $4
let the number of persons be p
and the total cost be C
The total cost function is expressed as
Step two:
Required:
<u><em>We want to make P subject of the cost function </em></u>
Take 20 to the other side we have
C-20=4p
divide through by 4
P=C-20/4
simplify
P=C/4-5
<h2>
Greetings!</h2>
Answer:
Option 4
Step-by-step explanation:
Firstly, we need to make the two x's or the two y numbers the same. Lets multiply the second equation by 2:
(2x + 3y = 5 ) * 2 =
4x + 6y = 10
Now, subtract the second equation from the first one:
(4x - y = -11) - (4x + 6y = 10)
4x - 4x = 0
-y - 6y = -7y
-11 - 10 = -21
-7y = -21
Divide both sides by -7:
y = 3
Plug 3 into the first equation as y:
4x - 3 = -11
4x = -11 + 3
4x = -8
x = -2
So x = -2 and y = 3. We need to find one of the options that equals this.
<h3>Option 1)</h3>
-4x - 9y = -21
-10y = -30
40x - 90y = -210
-90y = -270
40x - 0 = 40x
-90y - - 90y = -90 + 90 = 0y
-210 - -270 = -210 + 270 = 60
40x = 60
x = 1.5
We already know this isn't equivalent because the x value is not the x value of the given equation.
<h3>Option 2) </h3>
4x + 3y = 5
2y = -6
_______
8x + 6y = 10
6y = -18
8x - 0 = 8x
6y - 6y = 0
10 - -18 = 10 + 18 = 28
8x = 28
x = 3.5
So we know this isn't equivalent because again, the x value isn't the same as the given equation.
<h3>Option 3</h3>
7x - 3y = -11
9x = -6
-----------
63x - 27y = -99
63x = -42
----------------
63x - 63x = 0
-27y - 0 = -27y
-99 - - 42 = -99 + 42 = -57
-27y = -57
-9y = -19
9y = 19
y = 19/9
So we know this one isn't equivalent as the y value isn't the same as the given equation.
<h3>Option 4</h3>
12x - 3y = -33
14x = -28
x = -28/14 = -2
12(-2) - 3y = -33
-24 - 3y = -33
-3y = -33 + 24
-3y = -9
y = 9/3
y = 3
So x = -2 and y = -3 which is the same as the first equation.
<h2>Hope this helps!</h2>
