I would add them together to get 73
Step-wise I would add the ones column together to get 13, carry the one over then add the tens up to get 70 - your answer is 73
What line? I can't see any image.
The idea of grouping is to get the terms in groups that allow you to factor out from each group something that becomes a factor in itself, leaving two factors behind that are alike. Like this: rearrange those terms so they are in this order:
(-70y^2 - 63xy) + (90x^3 + 100yx^2). Now out of the first set we are going to factor out a -7y, and out of the second set we are going to factor out a 10x^2. When we do this, this is what we get: -7y(10y + 9x) + 10x^2(9x + 10y). As you can see, what's inside both sets of parenthesis is the same, just in a different order. We can factor that out now, leaving (9x + 10y)(10x^2 - 7y). And that is factored by grouping.
Answer:
a) 20.16; b) 20.49 and 21.51
Step-by-step explanation:
We use z scores for each of these. The formula for a z score is
.
For part a, we want the 20th percentile; this means we want 20% of the data to be lower than this. We find the value in the cells of the z table that are the closest to 0.20 as we can get; this is 0.2005, which corresponds with a z score of -0.84.
Using this, 21 as the mean and 1 as the standard deviation,
-0.84 = (X-21)/1
-0.84 = X-21
Add 21 to each side:
-0.84+21 = X-21+21
20.16 = X
For part b, we want the middle 39%. This means we want 39/2 = 19.5% above the mean and 19.5% below the mean; this means we want
50-19.5 = 30.5% = 0.305 and
50+19.5 = 69.5% = 0.695.
Looking these values up in the cells of the z table, we find those exact values; 0.305 corresponds with z = -0.51 and 0.695 corresponds with z = 0.51:
-0.51 = (X-21)/1
-0.51 = X-21
Add 21 to each side:
-0.51+21 = X-21+21
20.49 = X
0.51 = (X-21)/1
0.51 = X-21
Add 21 to each side:
0.51+21 = X-21+21
21.51 = X
Answer:
71°
Step-by-step explanation:
In order to be able to solve this problem, we must assume the relation between lines "a" and "b" is that they are parallel.
If a║b, then ∠1 and ∠2 are corresponding, hence congruent.
m∠1 = m∠2 = 71°