Answer:
x = -2/15.
Step-by-step explanation:
Finding the second derivative:
f'(x) = 15x^2 +4x - 3
f"(x) = 30x + 4
30x + 4 = 0 for a point of inflection
x = -4/30 = -2/15
So 30x + 4 is negative up to x = -2/15 and positive thereafter.
So the curve passes from concave downward to concave upward at x = -2/15.
You can’t solve the equation with a graph but there is a substitution or it.
Simplify 3(−y − 4) + 4.
Y= -3y - 8
X= -y - 4
Answer: d-9
Step-by-step explanation: d equals the savings so it says she spent four dollars and then five, so just add those and subtract it from the savings
Represent 'a number' by x
7 times x equals 9 more than 4 times x
7 times x=9+4 times x
7x=9+4x
subtract 4x from both sides
3x=9
divide 3
x=3
the number is 3
Answer:
r = -1 9/20
Step-by-step explanation:
-2 1/4 = r - 4/5
Switch sides:
r - 4/5 = -2 1/4
Add 4/5 to both sides.
r = -2 1/4 + 4/5
Change the mixed numeral into a fraction:
r = -9/4 + 4/5
The LCD is 20.
r = -45/20 + 16/20
r = -29/20
r = -1 9/20