Domain: (-∞,∞) or All real numbers
Range: (-∞,∞) or All real numbers
Answer:
Step-by-step explanation:
We can directly substitute y of the first equation to the second equation.
-2x - 1 = 3x - 16
5x = 15
x = 3
Substituting back to any of the two equations, we get y = -2(3)-1 = -7. If you check with the second equation, y = 3(3)-16 = -7 as well.
Therefore .
Hello,
x²/25+y²/9=1
a=5, b=3 c²=a²-b²=25-9=16=4²
Foci are (0,4) and (0,-4)
Answer C
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Answer:
i dont know
Step-by-step explanation:
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)
