Answer:
<h3>x = 3/2 ± √(61/20)</h3>
Step-by-step explanation:
5x² - 15x - 4 = 0
Add 4 to both sides.
5x² - 15x = 4
The coefficient of 5x² is 5, divide both sides by 5.
x² - 3x = 4/5
The coefficient of -3x is -3. Let b=-3.
Then we need to add (b/2)^2=9/4 to both sides to complete the square.
Add 9/4 to both sides.
x² - 3x + 9/4 = 61/20
Factor left side.
(x-3/2)² = 61/20
Take square root of both sides.
x-3/2 = ± √(61/20)
Add 3/2 to both sides.
x = 3/2 ± √(61/20)
Answer:
x= 5
Step-by-step explanation:
both lines are the same length
5x-6=2x+9
-2x -2x
3x-6= +9
+6 +6
3x = 15
÷3 ÷3
x= 5
<h2>

</h2>
Total surface area of cone is 176π
<h3>Explanation:</h3>
Surface area of curved surface of a cone is give by π⋅r.l , where r is the radius and l is the slant height of the cone.
Hence surface area of curved surface of a cone is π×8×14=112π .
As surface area of base is π×82=64π .
Hence total surface area is 112π+64π=176π
Answer:
3x + x + 100° = 180°
⇔ 4x = 80°
⇔ x = 20°
Step-by-step explanation: