Answer:
the second choice is correct
Step-by-step explanation:
The equation of a line in slope- intercept form is
y = mx + c ( m is the slope and c the y- intercept )
y = 
x - 9 is in this form
with slope m =
• Parallel lines have equal slopes, hence
y = x + c ← is the partial equation of the parallel line
To find c substitute (- 8, - 18) into the partial equation
- 18 = - 6 + c ⇒ c = - 18 + 6 = - 12
y = x - 12 ← equation of parallel line
Answer:
Step-by-step explanation:
f(x)= (x - 3)(x - 5)
f(x) = x^2 - 5x - 3x + 15
f(x) = x^2 - 8x + 15
Answer is A
Answer:
Its a right triangle
Step-by-step explanation:
Answer:
(
f
+
g
)
(
x
)
=
3
x
2
+
x
+
2
Explanation:
(
f
+
g
)
(
x
)
=
f
(
x
)
+
g
(
x
)
:
(
f
+
g
)
(
x
)
=
3
x
2
−
x
+
5
+
2
x
−
3
Add like terms:
(
f
+
g
)
(
x
)
=
3
x
2
+
(
−
x
+
2
x
)
+
(
5
−
3
)
(
f
+
g
)
(
x
)
=
3
x
2
+
x
+
2
(
f
+
g
)
(
x
)
=
3
x
2
+
x
+
2
Explanation:
(
f
+
g
)
(
x
)
=
f
(
x
)
+
g
(
x
)
:
(
f
+
g
)
(
x
)
=
3
x
2
−
x
+
5
+
2
x
−
3
Add like terms:
(
f
+
g
)
(
x
)
=
3
x
2
+
(
−
x
+
2
x
)
+
(
5
−
3
)
(
f
+
g
)
(
x
)
=
3
x
2
+
x
+
2
(
f
+
g
)
(
x
)
=
3
x
2
+
x
+
2
Explanation:
(
f
+
g
)
(
x
)
=
f
(
x
)
+
g
(
x
)
:
(
f
+
g
)
(
x
)
=
3
x
2
−
x
+
5
+
2
x
−
3
Add like terms:
(
f
+
g
)
(
x
)
=
3
x
2
+
(
−
x
+
2
x
)
+
(
5
−
3
)
(
f
+
g
)
(
x
)
=
3
x
2
+
x
+
2
Step-by-step explanation:
F(x) = 18-x^2 is a parabola having vertex at (0, 18) and opening downwards.
g(x) = 2x^2-9 is a parabola having vertex at (0, -9) and opening upwards.
By symmetry, let the x-coordinates of the vertices of rectangle be x and -x => its width is 2x.
Height of the rectangle is y1 + y2, where y1 is the y-coordinate of the vertex on the parabola f and y2 is that of g.
=> Area, A
= 2x (y1 - y2)
= 2x (18 - x^2 - 2x^2 + 9)
= 2x (27 - 3x^2)
= 54x - 6x^3
For area to be maximum, dA/dx = 0 and d²A/dx² < 0
=> 54 - 18x^2 = 0
=> x = √3 (note: x = - √3 gives the x-coordinate of vertex in second and third quadrants)
d²A/dx² = - 36x < 0 for x = √3
=> maximum area
= 54(√3) - 6(√3)^3
= 54√3 - 18√3
= 36√3.
