Answer:
a = - 2, b = - 6
Step-by-step explanation:
Substitute the values of the zeros into the polynomial and equate to zero.
x² +(a + 1)x + b
x = - 2 → (- 2)² - 2(a + 1) + b = 0 , that is
4 - 2a - 2 + b = 0
2 - 2a + b = 0 ( subtract 2 from both sides )
- 2a + b = - 2 → (1)
x = 3 → 3² + 3(a + 1) + b = 0, that is
9 + 3a + 3 + b = 0
12 + 3a + b = 0 ( subtract 12 from both sides )
3a + b = - 12 → (2)
Subtract (1) from (2) term by term to eliminate b
5a = - 10 ( divide both sides by 5 )
a = - 2
Substitute a = - 2 into either of the 2 equations and evaluate for b
Substituting into (2)
3(- 2) + b = - 12
- 6 + b = - 12 ( add 6 to both sides )
b = - 6
Thus a = - 2 and b = - 6
Attached solutions and work.
Answer:
x=16
Step-by-step explanation:
multiply both sides of the equation by 2
multiply the number
reduce the number
Answer:
a) The formula for the area of a circle
Step-by-step explanation:
The formula for the area of a circle is
A = πr²
π is an irrational number and, no matter what value you use for r, the area will be an irrational number,
b) is wrong. A = ½(a + b)h.
c) is wrong. A = ½bh.
d) is wrong. A = bh.
All measurements are rational numbers, so the areas will be rational numbers.
