Answer:
d
Step-by-step explanation:
Using the Cosine rule to find ∠ A
cosA = 
= 
= 
= 
, then
∠ A = 
( ) ≈ 84.9° ( to 1 dec. place )
Answer:
stratified sample
Step-by-step explanation:
Answer:
4x is the greatest common factor of those two.
Step-by-step explanation:
(-16x + 12x)
4x (-4 + 3)
4x is the GCF
Why you may ask is 4x the GCF because when you divide 4x from both you're left with -4 + 3...... you can't take out the negative from the 16 because when you check your work negative 4x times 3 gives you negative 12x which isn't the equation you started with. So positive 4x times 3 give you 12x.
Hopes this helps!!!
Answer:
9*(6+7)
Step-by-step explanation:
First, we have to find the Greatest Common Factor (GCF), to do this we have to see all the factors of 54 and 63 and find the greatest factor that they have in common.
Factors of 54
1,2,3,6,9,18,27,54
Factors of 63
1,3,7,9,21,63
The GCF is 9 because is the greatest factor that is common to both numbers.
Now we have to divide 54/9 and 63/9
54/9 = 6
63/9 = 7
So now we can write the product of the GCF and another sum:
9*(6+7)
<em>We can prove this by solving both expressions:</em>
<em>54+63 = 9*(6+7)</em>
<em>117 = 9*13</em>
<em>117 = 117 </em>
<em>The results are equal so we prove it is right.</em>
There are 9 two-year-olds and 18 each of 3 and 4 year olds.
To solve this we could write and solve the equation below, letting x be the number of 3 and 4 year olds.
x/2 + x + x = 45
x + 2x + 2x = 90
5x = 90
x = 18
From here, we just divide 18 by 2 to get the number of 2 year olds.
