Answer:
We are effectively looking for a and b such that 5, a, b, 135 is a geometric sequence.
This sequence has common ratio <span><span>3<span>√<span>1355</span></span></span>=3</span>, hence <span>a=15</span> and <span>b=45</span>
Explanation:
In a geometric sequence, each intermediate term is the geometric mean of the term before it and the term after it.
So we want to find a and b such that 5, a, b, 135 is a geometric sequence.
If the common ratio is r then:
<span><span>a=5r</span><span>b=ar=5<span>r2</span></span><span>135=br=5<span>r3</span></span></span>
Hence <span><span>r3</span>=<span>1355</span>=27</span>, so <span>r=<span>3<span>√27</span></span>=3</span>
Then <span>a=5r=15</span> and <span>b=ar=15⋅3=45</span>
Answer:
Are the sides parallel?
Step-by-step explanation:
Given:
She purchased adult ticket for herself and children tickets for her 2 boys.
Cost of one adult ticket = $39.99
Cost of one child ticket = $19.99
To find:
The expression to represent the total cost of the tickets Jenny purchased.
Solution:
Let x represent the number of adult ticket purchase
and y represent the number of child tickets purchase.
Cost of one adult ticket = $39.99
Cost of one child ticket = $19.99
Total cost = 39.99x + 19.99y
Therefore, the expression for total cost is 39.99x + 19.99y.
She purchased one adult ticket and 2 child tickets.
Substitute x=1 and y=2 in the above expression.
Total cost = 39.99(1) + 19.99(2)
= 39.99 + 39.98
= 79.97
Therefore, the required expression to represent the total cost of the tickets Jenny purchased is 39.99(1) + 19.99(2) and total cost is $79.97.
You can use elimination
7x - 3y = 4
-10x + 3y = 2
Add both equations
-3x = 6, x = -2
Plug in -2 for x in one equation
7(-2) - 3y = 4
-14 - 3y = 4
-3y = 18, y = -6
Solution: x = -2, y = -6