SOLUTION:
Let whole number = x
x + 2x^2 = 21
2x^2 + x - 21 = 0
2x^2 + 7x - 6x - 21 = 0
x ( 2x + 7 ) - 3 ( 2x + 7 ) = 0
( 2x + 7 ) ( x - 3 ) = 0
2x + 7 = 0
2x = - 7
x = - 7 / 2
OR
x - 3 = 0
x = 3
ANSWER:
Therefore, as 3 is a whole number while - 7 / 2 isn't a whole number, the whole number must be 3.
Hope this helps! :)
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Answer:
c = 2 or c = -2
Step-by-step explanation:

Hope this helps.
Answer:
The required point is P(-7,
) where, x-coordinate twice the y-coordinate on line 2x - 6y = 7
Step-by-step explanation:
Given equation of line is 2x-6y=7
To find point on graph whose x-coordinate twice the y-coordinate:
Let y be y-coordinate of point
Hence, x-coordinate of point will be 2y
The required point is P(2y,y) on equation of line 2x-6y=7
Now,
2x-6y=7
2(2y)-6y=7
-2y=7
y=
Thus,
The required point is P(-7,
)
Note: Figure show equation of line red line and point P as blue dot.
Answer:
<em><u>A.10000</u></em>
<em><u>B.25 more trees must be planted</u></em>
Step-by-step explanation:
⇒Given:
- The intial average yield per acre
= 150
- The initial number of trees per acre
= 100
- For each additional tree over 100, the average yield per tree decreases by 1 i.e , if the number trees become 101 , the avg yield becomes 149.
- Total yield = (number of trees per acre)
(average yield per acre)
<em>A.</em>
⇒If the total trees per acre is doubled , which means :
total number of trees per acre
=
= 200
the yield will decrease by :
- 

⇒total yield = 
<em>B.</em>
⇒to maximize the yield ,
let's take the number of trees per acre to be 100+y ;
and thus the average yield per acre = 150 - y;
total yield = 
this is a quadratic equation. this can be rewritten as ,
⇒ 
In this equation , the total yield becomes maximum when y=25;
<u><em>⇒Thus the total number of trees per acre = 100+25 =125;</em></u>
$13, 666.67
because you would do 820 divided by 0.06 and you get 13,666.6667 which you round to 13,666.67