Answer:
r(-1) = 6.31 and r(2) = -16.88
Step-by-step explanation:
* Lets read the problem and solve it
- Evaluate means find the value, so evaluate r(x) means find the value
of it at the given values of x
∵ r(x) = -0.21x³ + x² - 8.1x - 3
∵ x = -1 and x = 2
- Then find r(-1) by substitute x by -1 and find r(2) by substitute x by 2
# At x = -1
∴ r(-1) = -0.21(-1)³ + (-1)² - 8.1(-1) - 3
∴ r(-1) = -0.21(-1) + (1) - 8.1(-1) - 3
∴ r(-1) = 0.21 + 1 + 8.1 - 3
∴ r(-1) = 6.31
# At x = 2
∴ r(2) = -0.21(2)³ + (2)² - 8.1(2) - 3
∴ r(2) = -0.21(8) + (4) - 8.1(2) - 3
∴ r(2) = -1.68 + 4 - 16.2 - 3
∴ r(2) = -16.88
* r(-1) = 6.31 and r(2) = -16.88
Answer:
a) add x , subtract 1 and divide by 4
The solution of given equation 
<u>Step-by-step explanation:</u>
Given equation 1+3 x = -x +4
<em> Add 'x' on both sides , we get</em>
1 + 3 x + x = - x + x +4
1 + 4 x = 4
<em> Subtract '1' on both sides , we get</em>
<em> 1+4 x -1 = 4 -1</em>
4 x = 3
<em> Dividing '4' on both sides, we get</em>


<u><em>Final answer</em></u>:-
<em>The solution of given equation </em>
<em></em>
Answer:
-17
Step-by-step explanation:
It is basically subtracting 4 from 21 except the answer is negative
Answer:
3 and 10
Step-by-step explanation:
3 plus 10 equals 13
3 times 10 equals 30