Answer:
A.
Step-by-step explanation:
Take a look at what happens when squaring either of these...
Notice a couple of patterns.
1. The last term has a positive coefficient. That rules out answer choices C and D.
2. The coefficient of the middle term is either . So what are <em>a</em> and <em>b</em>? <em>a</em> is the square root of the x^2 term and <em>b</em> is the square root of the y^2 term.
The middle coefficient needs to be either +30 or -30. The answer is choice A.
Answer:
The Pythagorean identity states that
Using that we can rewrite the left denominator as:
Which can be factored as
The numerator we can expand as:
On the right hand side, let's multply numerator and denominator with (1 - sin t):
The total formula then becomes:
There you go... left and right are equal.
Answer:
The standard form of the quadratic equation is x² + 3·x - 4 = 0
Step-by-step explanation:
The standard form of a quadratic equation is a·x² + b·x + c = 0
Given that the expression of the quadratic equation is (x + 4)·(x - 1) = y, we can write the given expression in standard form by expanding, and equating the result to zero as follows;
(x + 4)·(x - 1) = x² - x + 4·x - 4 = x² + 3·x - 4 = 0
The standard form of the quadratic equation is x² + 3·x - 4 = 0
The graph of the equation created with MS Excel is attached
