Answer: 54.4 mph
Step-by-step explanation:
First find the distance to the train station. If it took Carlos 4 hours to come back driving at 68 mph, the distance is:
= Speed * time
= 68 * 4
= 272 miles
This means that Carlos drove for 5 hours to cover 272 miles the first time. His average speed was therefore:
= Distance / time
= 272/5
= 54.4 mph
Answer: You can multiply the top equation by -1 to eliminate the x variable.
And the solution is (2,4/3) in case you need it.
Step-by-step explanation:
2x + 3y = 8
2x + 6y = 12
If you multiply the upper equation or down equation by one, you will be able to eliminate the x variable.
-1( 2x + 3y) = -1(8) New equation: -2x -3y = -8.
Add the new equation you got by multiplying the top equation by -1 to the bottom equation.
Add them: -2x -3y = -8
2x + 6y = 12
3y = 4
y = 4/3
You can now input the value for y into the one of the equations and solve for x.
-2x - 3(4/3) = -8
-2x -4 = -8
+4 +4
-2x = -4
x = 2
Answer:
A,B,andE
Step-by-step explanation:
Or The length AB is 2, The length A'B' is 3, and The scale factor is Two-Thirds
Answer:
A 5
Step-by-step explanation:
Parts on the left have the same ratio as parts on the right.
... x/(x+5) = (x -2)/(x +1)
Multiplying by (x+5)(x+1), we get
... x(x +1) = (x -2)(x +5)
... x² +x = x² +3x -10 . . . . eliminate parentheses
... 0 = 2x -10 . . . . . . . . . . subtract x²+x
... 0 = x -5 . . . . . . . . . . . . divide by 2
... 5 = x . . . . . . . . . . . . . . . add 5
Multiplication is a simple way of adding
For example 6x8 is the same as 8+8+8+8+8+8
Any number multiplied by 1 is itself E.g 4x1 = 4
Multiplying by 2 is just doubling
Multiplying by 10 is adding a 0 to the original number
If it is a big number that you do not know how to multiply mentally split it up
E.g 17x13
Split 13 into 10 and 3
17x10= 170
17x3= 51
Then add these numbers
221
If you ever get stuck, use the long method, add them instead, you will get to the right answer but it will take longer
Dividing is not as simple
Like multiplication dividing by one will leave you with the same answer
Dividing by two means you half the number, which may give you a decimal
Bigger numbers are trickier, and you may be allowed to use a calculator for numbers
Below are a number of links, these websites will teach you how to improve your multiplication and division skills:
http://www.bbc.co.uk/schools/gcsebitesize/maths/number/decimalsrev3.shtml
https://m.youtube.com/watch?v=XiXeu9FxAcQ
https://www.tutorialspoint.com/multiply_and_divide_whole_numbers/multiplication_as_repeated_addition.htm
