Answer:
38cm
Step-by-step explanation:
1. The perimeter of a square can be found with the formula
2. Since its length and width are whole numbers, it must be either
1 x 18,
2 x 9 or
3 x 6
3. Using the formula in step 1, we can found that the perimeter in these cases are
38
22
18
respectively
4. Compare those perimeter we found in previous step, it's obvious that the greatest is 38. Solved.
Answer:
a) 5 b) 1 c) 0 d) -4
Explanation:
a) 10[(1/2+1/4) + 2(1/8)] ÷ 2
Ok, there's a lot going on. You will want to follow PEMDAS, the acronym of the Order of Operations. It stands for Parentheses, Exponents, Multiplication/Division, and Addition/Subtraction. The M/D can be switched depending on what comes first from left to right, and same goes for A/S.
First, start off by doing everything in the brackets.
Let's add 1/2 and 1/4. To add fractions, they have to have a common denominator. I'm making 1/2 into 2/4 but multiplying the top and bottom by 2. Now it is 2/4 + 1/4 so we can add to get <u>3/4</u>.
The other thing inside the brackets is 2(1/8). We can just multiply straight across and get 2/8. This can be simplified to <u>1/4</u>.
Now, we add 3/4 and 1/4. The denominators are already the same, so we can just add them together to get 4/4 or 1.
Rewriting the equation, we now have 10(1)÷2
10•1 = 10
10 ÷ 2 = 5
The answer to question a is <u><em>5</em></u>.
b) √(0.6)² + (0.8)²
First, we need to square both terms. Squaring is the same as multiplying the number by itself.
0.6 • 0.6 = 0.36
0.8 • 0.8 = 0.64
Add them together: 0.36 + 0.64 = 1
√1 = 1
The answer to question b is <u><em>1</em></u>.
c) (1/5 - 3/5) • √6•3/2 + (√36 ÷ √5²)
Let's start with the first bit: (1/5 - 3/5)
The denominators are the same, so just subtract and you get <u>-2/5</u>
The second bit now:
Multiply across and you get 18/2, which can be simplified to 9
√9 = <u>3</u>
The third section: (÷
)
The square root of 36 = 6 (because 6•6=36, so it's right)
The square root and the square cancel each other out, so the second part is 5.
6 ÷ 5 = <u>1.2</u>
Now put it all together: -2/5 • 3 + 1.2
I'm making the 1.2 into a fraction so it is the same as the fraction: 1.2 = 6/5
We now have -2/5 • 3 + 6/5
First we multiply -2/5 and 3 across:
-2/5 • 3 = -6/5
Now we add -6/5 and 6/5 across:
-6/5 + 6/5 = <u><em>0</em></u>
d) [-1.5 + √0.25 - (-0.75)] • 2^4
Doing the brackets first:
The square root of 0.25 = 0.5 (because 0.5 • 0.5 = 0.25)
-1.5 + 0.5 - -0.75
-1 + 0.75 (subtracting a negative make a positive)
-0.25
-0.25 • 2^4
2^4 = 16 (this is saying 2•2•2•2 which is 16)
-.25 • 16 = <u><em>-4</em></u>