Answer:
the answer is in the image if you have any questions let me know
Step-by-step explanation:
Answer:
C
Step-by-step explanation:
The equation of a parabola in vertex form is
y = a(x - h)² + k
where (h, k) are the coordinates of the vertex and a is a multiplier
Given
y = 2x² + 12x + 1
To express in vertex form use the method of completing the square.
The coefficient of the x² term must be 1 , thus factor out 2 from 2x² + 12x
y = 2(x² + 6x) + 1
add/ subtract ( half the coefficient of the x- term)² to x² + 6x
y = 2(x² + 2(3)x + 9 - 9) + 1
= 2(x + 3)² - 18 + 1
= 2(x + 3)² - 17 → C
Simplifying
5x + 2(8x + -9) = 3(x + 4) + -5(2x + 7)
Reorder the terms:
5x + 2(-9 + 8x) = 3(x + 4) + -5(2x + 7)
5x + (-9 * 2 + 8x * 2) = 3(x + 4) + -5(2x + 7)
5x + (-18 + 16x) = 3(x + 4) + -5(2x + 7)
Reorder the terms:
-18 + 5x + 16x = 3(x + 4) + -5(2x + 7)
Combine like terms: 5x + 16x = 21x
-18 + 21x = 3(x + 4) + -5(2x + 7)
Reorder the terms:
-18 + 21x = 3(4 + x) + -5(2x + 7)
-18 + 21x = (4 * 3 + x * 3) + -5(2x + 7)
-18 + 21x = (12 + 3x) + -5(2x + 7)
Reorder the terms:
-18 + 21x = 12 + 3x + -5(7 + 2x)
-18 + 21x = 12 + 3x + (7 * -5 + 2x * -5)
-18 + 21x = 12 + 3x + (-35 + -10x)
Reorder the terms:
-18 + 21x = 12 + -35 + 3x + -10x
Combine like terms: 12 + -35 = -23
-18 + 21x = -23 + 3x + -10x
Combine like terms: 3x + -10x = -7x
-18 + 21x = -23 + -7x
Solving
-18 + 21x = -23 + -7x
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '7x' to each side of the equation.
-18 + 21x + 7x = -23 + -7x + 7x
Combine like terms: 21x + 7x = 28x
-18 + 28x = -23 + -7x + 7x
Combine like terms: -7x + 7x = 0
-18 + 28x = -23 + 0
-18 + 28x = -23
Add '18' to each side of the equation.
-18 + 18 + 28x = -23 + 18
Combine like terms: -18 + 18 = 0
0 + 28x = -23 + 18
28x = -23 + 18
Combine like terms: -23 + 18 = -5
28x = -5
Divide each side by '28'.
x = -0.1785714286
Simplifying
x = -0.1785714286
Answer:
Option B is correct.i.e.,
Step-by-step explanation:
Given: Pyramid with equilateral triangle as base
Length of side of equilateral triangle = s unit
to find: height of equilateral triangle
Here we use a property of equilateral triangle.
Perpendicular from a vertex on a side and median of that side of a triangle is same in equilateral triangle.
All heights are of equal length. So, we just need to find one height or length of 1 altitude.
Figure of base triangle is attached
In Δ ABC
AB = BC = AC = s unit
AD is height
BD = 
Now, In Δ ABD
using pythagoras theorem
BD² + AD² = AB²
Therefore, Option B is correct.i.e., 
