Answer:
70 degrees
Step-by-step explanation:
Angle BZA = Angle BZC = 20 degrees
Reason : These two angles are Vertically opposite angles.
Angle BZA + Angle BZC = 90
20 + Angle BZC = 90
Angle BZC = 90 - 20
Angle BZC = 70 degrees
The answer is 77. if you do it the opposite way and multiply
When roots of polynomials occur in radical form, they occur as two conjugates.
That is,
The conjugate of (a + √b) is (a - √b) and vice versa.
To show that the given conjugates come from a polynomial, we should create the polynomial from the given factors.
The first factor is x - (a + √b).
The second factor is x - (a - √b).
The polynomial is
f(x) = [x - (a + √b)]*[x - (a - √b)]
= x² - x(a - √b) - x(a + √b) + (a + √b)(a - √b)
= x² - 2ax + x√b - x√b + a² - b
= x² - 2ax + a² - b
This is a quadratic polynomial, as expected.
If you solve the quadratic equation x² - 2ax + a² - b = 0 with the quadratic formula, it should yield the pair of conjugate radical roots.
x = (1/2) [ 2a +/- √(4a² - 4(a² - b)]
= a +/- (1/2)*√(4b)
= a +/- √b
x = a + √b, or x = a - √b, as expected.
The negative sign show the change in direction, that is the opposite side of the value.
In the number line, 1 is the opposite of -1, that is the digit from the left side is the opposite value of the right side.
Consider an object P is moving in positive x direction than on moving the object into its opposite direction, it will move along the negative x axis.
Answer : A) -