Answer:
C
Step-by-step explanation:
The n th term formula of a geometric sequence is
= a 
where a is the first term and r the common ratio
Using the second and fourth term, then
ar = 6 → (1)
ar³ = 54 → (2)
Divide (2) by (1)
=
= 9
r² = 9 ⇒ r =
= 3 → C
Answer:
x = 1, y = 2, z = -1
Step-by-step explanation:
2x + 4y = 10
2x = -4y + 10
x = -2y + 5
now sub -2y + 5 in for x, back into the other 2 equations
2x + 2y + 3z = 3 -3x + y + 2z = -3
2(-2y + 5) + 2y + 3z = 3 -3(-2y + 5) + y + 2z = -3
-4y + 10 + 2y + 3z = 3 6y - 15 + y + 2z = -3
-2y + 3z = 3 - 10 7y + 2z = - 3 + 15
-2y + 3z = - 7 7y + 2z = 12
-2y + 3z = -7....multiply by 2
7y + 2z = 12...multiply by -3
--------------------------
-4y + 6z = -14 (result of multiplying by 2)
-21y - 6z = -36 (result of multiplying by -3)
---------------------------add
-25y = - 50
y = -50/-25
y = 2 <===
2x + 4y = 10 2x + 2y + 3z = 3
2x + 4(2) = 10 2(1) + 2(2) + 3z = 3
2x + 8 = 10 2 + 4 + 3z = 3
2x = 10 - 8 6 + 3z = 3
2x = 2 3z = 3 - 6
x = 2/2 3z = -3
x = 1 <== z = -3/3
z = -1 <===
Answer:
x=4
Step-by-step explanation:
21x+6=90(alternate angles)
21x=90-6
x=94/21
Therefore, x=4
Answer:
G is cheapest at $815.15
Step-by-step explanation:
F-cost is 915
g cost is 85% (100-15=85%) so .85 x 959=815.15
h 1000-100=900
j 925-20=905.
The equation 7x + 3x - 18 = 6(x+3) is 9
<h3>What is equation?</h3>
An equation is a mathematical statement that is made up of two expressions connected by an equal sign.
given:
7x + 3x - 18 = 6(x+3)
7x + 3x - 18 = 6x+18 [Distributive Property]
10x-18= 6x+18 [Addition Property of Equality]
10x-6x= 18+18 [Combine Like Terms ]
4x=36 [Subtraction Property of Equality]
4*x=36 [Multiplication Property of Equality]
x=36/4 [Division Property of Equality]
x=9
Learn more about equation here:
brainly.com/question/10413253
#SPJ1