Can someone explain this pls
1 answer:
Answer:
Step-by-step explanation:
( g ° f )(x) = ( x + 7 )² = x² + 14x + 49
20 + 3(x² + 14x + 49) = - 34
20 + 3x² + 42x + 147 = - 34
3x² + 42x + 201 = 0 ⇔ x² + 14x + 67 = 0
D = 196 - 268 = - 72 < 0
There is no any roots in set of real numbers.
The values of x in set of complex numbers are:
=
±
= - 7 ± 3√2 i
You might be interested in
Answer:
see explanation
Step-by-step explanation:
Given the 3 equations
3x + 5y + 5z = 1 → (1)
x - 2y = 5 → (2)
2x + 4y = 11 → (3)
Use (2) and (3) to solve for x and y
Multiply (2) by 2
2x - 4y = 10 → (4)
Add (3) and (4) term by term
4x = 21 ( divide both sides by 4 )
x =
Substitute this value of x into (3)
2 × + 4y = 11
+ 4y = 11 ( subtract
from both sides )
4y = ( divide both sides by 4 )
y =
Substitute the values of x and y into (1) and solve for z
3 × + 5 ×
+ 5z = 1
+
+ 5z = 1
+ 5z = 1 ( subtract
from both sides )
5z = - ( divide both sides by 5 )
z = -
Solution is
x = , y =
, z = -