Answer:
a = -6
b = 1
Step-by-step explanation:
The gradient of the tangent to the curve y = ax + bx^3, will be:
dy/dx = a + 3bx²
at (2, -4)
dy/dx = a+3b(2)²
dy/dx = a+12b
Since the gradient at the point is 6, then;
a+12b = 6 ....1
Substitute x = 2 and y = -4 into the original expression
-4 = 2a + 8b
a + 4b = -2 ...2
a+12b = 6 ....1
Subtract
4b - 12b = -2-6
-8b = -8
b = -8/-8
b = 1
Substitute b = 1 into equation 1
Recall from 1 that a+12b = 6
a+12(1) = 6
a = 6 - 12
a = -6
Hence a = -6, b = 1
Let B = the weight of box B
Let 2B = the weight of box A
Let 2B + 30 = the weight of box C
B + 2B + 2B + 30 = 640
5B = 610
B = 122 pounds, weight of box B
2B = 2(122) = 244 pounds, weight of box A
2B + 30 = 2(122) + 30 = 274 pounds, weight of box C
hope this helps
Answer:
Median
Step-by-step explanation:
You need to arrange the numbers in order by size.
Then if there is an odd number of terms the median in the middle term. If there is is an even amount of terms then what you do is add 2 then divide by 2
Answer:
$69
Step-by-step explanation:
$115 x 0.4 = $46 discount
$115 - 46 = $69