Answer:
Step-by-step explanation:
1). x² - 8x
To convert this expression into a perfect square trinomial,
x² - 2(4x) + 4² = (x - 2)²
Therefore , 4² = 16 should be added.
Option (4) is the answer.
2). x² + 2x = 3
x² + 2(1)(x) = 3
x² + 2(1)(x) + 1 = 3 + 1 [By adding 1 on both the sides]
(x + 1)² = 4
x + 1 = ±2
x = -3, -1
Option (1) is the answer.
3). 3x²- 18x = 21
x² - 6x = 7
x² - 2(3x) = 7
x² - 2(3x) + 3² = 7 + 3²
(x - 3)² = 7 + 9
(x - 3)² = 16
x - 3 = ±4
x = -1, 7
Answer:
Y= -2x+7
Step-by-step explanation:
Answer:
Possible ways to paint the house is 108
Step-by-step explanation:
Total number of houses to be painted=4
Total number of colours to b used(red,blue,green and yellow)=4
Number of ways to paint the first house=4
Number of ways to paint the second house=3
Number of ways to paint the third house=3
Number of ways to paint the fourth house=3
Total number of ways to paint the 4 houses=4×3^3=108 ways.
The answers here would be:
16) c
17) a
