Answer:
see explanation
Step-by-step explanation:
The nth term of an AP is
= a₁ + (n - 1)d
where a₁ is the first term and d the common difference
Given a₅ is double a₇ , then
a₁ + 4d = 2(a₁ + 6d) , that is
a₁ + 4d = 2a₁ + 12d ( subtract a₁ from both sides )
4d = a₁ + 12d ( subtract 12d from both sides )
- 8d = a₁
The sum of n terms of an AP is
= 
[ 2a₁ + (n - 1)d ] , substitute values
= 
( 2(- 8d) + 16d)
= 8.5(- 16d + 16d)
= 8.5 × 0
= 0
Answer:
9 degrees
Step-by-step explanation:
given:
Initial temperature : 17 degrees
temperature change = reduction by 8 degrees (i.e - 8 degrees)
hence the final temperature
= initial temperature + temperature change
= 17 + (-8)
= 17 - 8
= 9 degrees
Answer:
Step-by-step explanation:
<u><em>b).</em></u>
2x² - 9x - 5 = ( x - 5 )( 2x + 1 )
3x² - 15x = 3x ( x - 5 )
= 
Answer:
x = 4√2
Step-by-step explanation:
<u><em>Find the value of x. Leave your answer in simplest radical form. The chord measures 14, the diameter measures 18. Hint: use pythagorean theorem</em></u>
To solve, we will follow the steps below:
using Pythagoras theorem
opposite² + adjacent² = hypotenuse²
14² + y² = 18²
196 + y² = 324
subtract 196 from both-side of the equation
196 -196 + y² = 324-196
y² =128
Take the square root of both-side
√y² = √128
y =√128
y = √64×2
y =√64×√2
y = 8√2
x = half of y
x = y/2
x = 8√2 ÷ 2
x = 4√2
