Answer:
A.
Step-by-step explanation:
you have to find the discriminant
b²-4ac for each equation
if discriminant < 0 no real solutions because will be negative under the squareroot whhan you try to find the roots
if discriminant = 0 there is only one solution
if discriminant > 0 two real solutions
for your given problems
A. discriminant =(-2)²-4*2*15 will be negative
Answer:
A. (6x + 7)(6x - 7)
Step-by-step explanation:
use difference of squares, which says a^2 - b^2 =(a+b)(a-b)
take the square roots of the two numbers, 6x and 7, and use them as a and b
Answer: 36 cm
Explanation: Use Pythagorean Theorem to solve the question: a^2+b^2=c^2
Remember
(x^m)(x^n)=x^(m+n)
and difference of 2 perfect squres
(a²-b²)=(a-b)(a+b)
and sum or difference of 2 perfect cubes
so
(x^3)(x^3)(x^3)=x^(3+3+3)=x^9
so
x^9=3*3*x^3
x^9=9x^3
minus 9x^3 both sides
0=x^9-9x^3
factor
0=(x^3)(x^6-9)
factor difference of 2 perfect squraes
0=(x^3)(x^3-3)(x^3+3)
factor differnce or sum of 2 perfect cubes (force 3 into (∛3)³)
0=(x³)(x-∛3)(x²+x∛3+∛9)(x+∛3)(x²-x∛3+∛9)
set each to zero
x³=0
x=0
x-∛3=0
x=∛3
x²+x∛3+∛9=0 has no solution
x+∛3=0
x=-∛3
x²-x∛3+∛9=0 has no solution
so the solutions are
x=-∛3, 0, ∛3
Whoever worded question made tha shi so confusing
