This is a very interesting problem. What makes it so interesting is that
there's so little actual math to it. The only big Math thing you need to know
in order to work with this question is the definition of "perimeter".
"Perimeter" means
"the distance all the way around the edge of something".
The problem GIVES you the length of all the sides of both triangles.
To find the perimeter of one triangle, just take the lengths of its three
sides and addum up.
The perimeter of the blue one is (7x+7) + (5x-4) + (4x+2) .
That's it ! That's the perimeter. Of course, they want you to write
it in simplest form, so you have to clean it up. Remove all of the
parentheses, add up all the 'x's, and add up all the plain numbers,
and you'll have a short, pretty expression.
Then do the same thing for the red one, and get its perimeter.
In part-b, they want you to find the difference between the two perimeters.
No problem. Just write (the blue perimeter) minus (the red perimeter),
and simplify THAT expression.
Now they want the actual perimeters when 'x' is 3.
No big deal. Just take each separate perimeter, write '3' in place of 'x',
and find the number that the expression becomes.
Just now, looking at the picture without writing anything down,
I got 53 for the blue one and 17 for the red one.
I could easily be wrong, so you definitely have to work them
out for yourself.
Answer:
B) 36/(y+4)
Step-by-step explanation:
Use the process of elimination.
A cannot work because we are changing the operation. Instead of dividing thirty-six by the sum of four and a number, we are dividing thirty-six by four, then adding the unknown number. This is not the same as the original expression, so we know it is not this.
Next, check C. C doesn't seem right either. Remember that, unlike multiplication and addition, you cannot flip the order in which the operation is being done and still get the same answer. C says four plus a number divided by thirty-six, which is entirely different from our original expression. So the answer is not C.
And finally, check D. D doesn't work either. With D, we are dividing thirty-six by a number, then adding it to thirty-six divided by four. This is not the same as our original expression, so D isn't it.
That leaves us with B. Does it work? Yes, because changing the y and the four still will give the same thing. And yes, because 36 is being divided by the sum of that number and four. So it is our answer.
Answer:
2/3
Step-by-step explanation:
5/6 - (1/8÷3/4)
=5/6 - (1/8 × 4/3)
=5/6 - ( 1/6)
=4/6
=2/3