Where are the following choices
Answer:
b) i) Curve A
ii) - 1.75
iii) x = 1 - √5 or x = 1 + √5
Step-by-step explanation:
b) i) We are given a function y = x² - 2x - 3 and the graph of this function is also shown in the side diagram.
The equation can be rearranged to y = (x - 1)² - 4
⇒ (x - 1)² = y + 4
Therefore, this is an equation of a parabola having the vertex at (1,-4) point and its axis is parallel to the positive y-axis.
So, the curve A represents the equation given. (Answer)
ii) Now, at x = 2.5, f(x) = 2.5² - 2 × 2.5 - 3 = - 1.75 (Answer)
iii) When y = 1, then x² -2x - 3 = 1
⇒ x² - 2x - 4 = 0
⇒ (x - 1)² - 5 = 0
⇒ (x - 1)² - (√5)² = 0
⇒ (x - 1 + √5)(x - 1 - √5) = 0
⇒ x = 1 - √5 or x = 1 + √5 (Answer)
Answer:
⅓x + y = 5⅓
or
⅓x + y = 5.3333333
or
⅓x + y = 16/3
Step-by-step explanation:
Solve for slope using rise/run
Y2 - Y1 / X2 - X1
(6) - (5) / (-2) - (1)
1 / -3
Slope: -⅓
y = -⅓x + b
solve for b using one of the points
I'll be using (1,5)
Substitute the point into the equation
5 = -⅓(1) + b
5 = -⅓ + b (add ⅓ to both sides)
+⅓ +⅓
5⅓ = b
5⅓ can also be written as 16/3 or 5.333333
The equation is now:
y = -⅓x + 5⅓
Convert to standard form by adding ⅓x to both sides
y = -⅓x + 5⅓
+⅓x +⅓x
Solution: ⅓x + y = 5⅓
Tanα=h/x, tanß=h/(x+88)
solving both for x
x=h/tanα, x=h/tanß-88, since x=x
h/tanα=h/tanß-88
h/tanß-h/tanα=88
(htanα-htanß)/(tanα*tanß)=88
h(tanα-tanß)/(tanα*tanß)=88
h=88(tanα*tanß)/(tanα-tanß)
Since α=32 and ß=22...
h=88(tan32*tan22)/(tan32-tan22)
h≈85.3 feet
