<span>2x - 3y - 3z = 8
We've been given the normal vector to the plane <2, -3, -3> and a point within the plane (1, -5, 3). In general if you've been given both the normal vector <a,b,c> and a point (e,f,g) within the plane, the expression for the plane will be:
ax + by + cz = d
and you can compute d by:
d = ae + bf + cg
So let's calculate d:
d = ae + bf + cg
d = 2*1 + -3*-5 + -3*3
d = 2 + 15 + -9
d = 8
And the equation for the plane is
2x - 3y - 3z = 8</span>
The ratio of pop songs to rock songs you download is 5:4, and 40 are pop songs. You want to find out how many rock songs there are.
First, add the ratios together: 5+4=9. This means that 9 will be your denominator, so 5/9 songs are pop and 4/9 songs are rock.
Now you know that pop songs account for 5/9 of the songs, this means that 40 is 5/9 of the total songs.
To find out how much 4/9 is, you need to divide 40 by 5 to get 1/9 and times that number by 4 to get 4/9:
40÷5=8×4=32 songs are rock songs
Have you got your answer yet?
Answer:
$8
Step-by-step explanation:
Answer:
≈ 58
Step-by-step explanation:
Estimation usually means you want an answer good to one or maybe two significant figures. That usually means you want to round the numbers involved to one or two significant figures.
Doing that here transforms the problem to 180/3 = 60, an answer with one significant figure.
You can improve the estimate a bit by recognizing that it is a little high (the numerator is higher than 175.32, but the denominator is the same). Since the numerator is high by about 5, the estimate is high by about 5/3 or a little less than 2. A closer estimate will be 60 - 2 = 58.
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The degree to which you refine the estimate will depend on the error requirements you have. Certainly an estimate of 60 is within 10% of the true value, so is "close enough" for many purposes.
