Carmen has given 6 coins to her brother<span />
Answer:
The correct options are:
A, B, and E.
Step-by-step explanation:
A mathematical sentence (or a mathematical statement) is a sentence that can be true or false.
This is the only criteria we need to check, now let's analyze each option.
A: 4 - d = 12
This can be true or false, for example, if d = 0 the sentence is false because:
4 - 0 = 12
4 = 12 is false.
and if d = -8 the sentence is true, because:
4 - (-8) = 12
4 + 8 = 12
12 = 12
is true.
B: 4 - V > 2
This sentence can be true or false, same reasoning as before, we can find values of V such that this is true or false.
C: 3 + 2
Now, here we can't say if this is true or false, so this is not a mathematical sentence.
D: 59
Same as before, this is just a number.
E: 6 + a = 13
This can be true or false, depending on the value of a, then this is a mathematical sentence.
F: 12*x
Here we can not say if this is true or false, so this is not a mathematical sentence.
The correct options are:
A, B, and E.
Answer:
10
Step-by-step explanation:
To solve this problem you need to create a system of equations. In these equations, use a = 2-seated car and b = 4- seated car
The first equation that you can make can be a + b = 25 because the number of 2-seated cars plus the number of 4-seated cars is going to equal a total of 25 cars.
The next equation you can make is 2a + 4b = 70 because the number of seats provided by the 2-seated cars plus the number of seats provided by the 4-seated cars will equal 70 total seats.
Next, line up the equations and solve:
Step one: Line up the equations
a + b = 25
2a + 4b = 70
Step two: Multiply the top equation by -2 so that you can add both of the equations together
-2(a) + -2(b) = 25(-2) ⇒ -2a - 2b = -50
2a + 4b = 70 ⇒ 2a + 4b = 70
Step three: Add the equations
-2a - 2b = -50
+ 2a + 4b = 70
______________
2b = 20
Step four: Divide both sides by 2 in order to solve for b
2b = 20 ⇒ b = 10
Because b represents the number of 4-seated cars, you now know that there are 10 4-seated cars on the ride.
