The subtraction theorem states that for all real numbers,
and
,
.
(To subtract, we can add the inverse.)
Thus, we can have the these two equivalent expressions.
Answer:
x = 5/2 thì y = 35 và x = -5 thì y = 5
Step-by-step explanation:
thay y = 4x + 25 vào phương trình y = 2x ^ 2 + 9x ta có:
4x + 25 = 2x ^ 2 + 9x
⇒2x ^ 2 + 5x - 25 = 0
⇒ x = 5/2 và x = -5
thay x = 5/2 vào phương trình y = 4x + 25 ⇒ y = 4*(5/2) + 25 = 35
thay x = -5 vào phương trình y = 4x + 25 ⇒ y = 4*(-5) + 25 = 5
Answer:
787.50
Step-by-step explanation:
interest=principle*rate*time/100
interest=3500*7.5*3/100
interest=35*7.5*3
interest=787.50
Answer:
A.
Step-by-step explanation:
Since you are trying to find <em>x</em>, you have to divide both sides by 4 to isolate <em>x</em> and get your answer.
The x coordinate of the vertex will be the average of the two zeros, here -3 and 5, so x=(-3+5)/2 = 1, f(1)=(1+3)(1-5) = -16.
Answer: (1, -16)
Let's do it some other ways. How about completing the square to turn f in to vertex form?
f(x) = (x+3)(x-5) = x² - 2x - 15 = (x² - 2x + 1) - 1 - 15 = (x-1)² - 16
and now we can read off (1, -16) as the vertex.
The other method is the vertex is x= - b/2a = - (-2)/2(1) = 1.
Three methods, same answer. Good.
