Step-by-step explanation:
problem 1.
1. 6y = 30
2. y = 5
3. 3x + 2(5) = 16
4. 3x+10=16
5. 3x=6
6. x=2
solution: (2,5)
problem 2.
1. x=7
2. 4(2)-2y=18
3. 28-2y=18
4. -2y= -10
5. y=5
solution (7,5)
problem 3
10x=10
x=1
7(1) +y =-2
y=-9
(1,9)
problem 4
0= -6
no solution
problem 5
0=0
Infinite many
Answer:
19 yards squared
Step-by-step explanation:
3x5=15
2x2=4
15+4=19
Part A: each tricycle has three wheels, so with 48 wheels the number of tricycles was a =48/3=16 tricycles.
t=w/3 (the number of tricycles is the number of wheels divided by 3)
Part B:
The number of seats:
24=b+a (so b=24-a)
The number of seats is the sum of one seat per bicycle and one seat per a tricycle
also, 61=2a+3b (the number of wheels)
So we have:
24=b+a
b=24-a
We can substitute this for b:
61=2a+3(24-a)
and solve:
61=2a+3*24-3a
61=72-a
a=72-61
a=11
There were 11 bicycles!!
and there were 24-11 tricycles, so 13 tricycles.
Part C: each of the bikes has only one front-steering handlebar, so there were a total of 144 vehicles:
a+b+c=144
There were 378 pedals. And the number of pedals is:
2a+2b+4c=378 (the numbers 2,2,4 represent the number of pedals per vehicle)
divide by 2:
a+b+2c=189
Now, we have
a+b+2c=189
and
a+b+c=144
and we can subtract them from each other:
a+b+c-(a+b+2c)=144-189
-c=45
c=45, so there were 45 tandem bicycles!
(this also means that a+b=144-45, that is a+b=99)
now the wheels:
3a+2b+2c=320
Let's substitute c:
3a+2b+90=320
which is
3a+2b=240
We also know that a+b=99, so we can substract this from this equation:
3a+2b+-a-b=240-99
2a+b=141
and again:
2a+b-a-b=141-99
a=42 - there were 42 trycicles!!!
And the bicycles were the rest:
99-42=57 bycicles
Answer:
12 kg
Step-by-step explanation:
15%×80 =
= 15×80/100
= 15×8/10
= 120/10
= 12 kg
Answer: 14
Step-by-step explanation:
28 times 0.5. First do 28 times 5. Then do 28 times 0. When multiplying with zeros, any number times zero, is zero. Your answer is 14.
