Answer:
C) 2(x+1)=2x+1 ( No Solution )
Step-by-step explanation:
1)
2)
3)
4)
~
Answer:
A
Step-by-step explanation:
Joint variation is given by:
Where k is some constant.
We are given that y = 360 when x = 4 and z = 10. Therefore:
Solving for k:
Therefore, our equation is:
Then when x = 5 and z = 12:
The answer is A.
Answer:
2. Judy =$5
Ben= $4
Step-by-step explanation:
2. Let Judy = x and Ben = y
8x + 10y = 80
9x + 5y = 65
Solve these simultaneous equations.
8
x + 10
y = 80
18
x + 10
y = 130
Take the second equation away from the first equation
−
10
x = −
50
x = 5
This means that Judy gets paid $5 an hour.
Therefore, Ben gets paid $4 an hour.
Answer:
3. 24 quarters and 16 dimes
Step-by-step explanation:
3. Let the number of dimes = x and the number of quarters = y
Value Value
Type Number of of
of of EACH ALL
coin coins coin coins
-------------------------------------------
dimes x $0.10 $0.10x
quarters y $0.25 $0.25y
-------------------------------------------
TOTALS 40 $7.60
x + y = 40
0.10x + 0.25y = 7.60
Get rid of decimals by multiplying every term by 100:
10x + 25y = 760
So we have the system of equations:
x + y = 40
10x + 25y = 760
We solve by substitution. Solve the first equation for y:
x + y = 40
y = 40 - x
Substitute (40 - x) for y in 10x + 25y = 760
10x + 25(40 - x) = 760
10x + 1000 - 25x = 760
-15x + 1000 = 760
-15x = -240
x = 16 = the number of dimes.
Substitute in y = 40 - x
y = 40 - (16)
y = 24 quarters.
$1.60 + $6.00 = $7.60
I hope that helped, sorry for taking so long :-)
Answer:
If b=-3 then the first expression is equal to 24 and the second expression is equal to -14.
If b=-2 then the first expression is equal to 8 and the second expression is equal to -36.
If b=10 then the first expression is equal to 440 and the second expression is equal to 324.
Yes, it is true.
Step-by-step explanation:
b=-3:
4b(b+1)=4(-3)(-3+1)=-12(-2)=24
(2b+7)(2b-8)=(2(-3)+7)(2(-3)-8)=(-6+7)(-6-8)=1(-14)=-14
b=-2:
4b(b+1)=4(-2)(-2+1)=-8(-1)=8
(2b+7)(2b-8)=(2(-2)+7)(2(-2)-8)=(-4+7)(-4-8)=3(-12)=-36
b=10:
4b(b+1)=4(10)(10+1)=40(11)=440
(2b+7)(2b-8)=(2(10)+7)(2(10)-8)=(20+7)(20-8)=27(12)=324
