-3 because 4 times -3 = -12 -7=-19
Answer:
16. (4 + h)( 11 + h)
17. (2 - x)(20 - x)
18. (2 + x)(- 12 + x)
19. (6 + m)(- 7 + m)
20. x =4 and 3
21. x = 9 and -3
Step-by-step explanation:
16. 44 + 15h + h² = 44 + 11h + 4h + h² = (4 + h)( 11 + h) (Answer)
17. 40 - 22x + x² = 40 - 20x - 2x + x² = (2 - x)(20 - x) (Answer)
18. - 24 - 10x + x² = - 24 - 12x + 2x + x² = (2 + x)( - 12 + x) (Answer)
19. - 42 - m + m² = - 42 - 7m + 6m + m² = (6 + m)(- 7 + m) (Answer)
20. x² - 7x + 12 = 0
⇒ x² - 4x - 3x + 12 = 0
⇒ (x - 4)( x - 3) = 0
⇒ x =4 and 3 (Answer)
21. x² - 6x = 27
⇒ x² - 6x -27 = 0
⇒ x² - 9x + 3x - 27 = 0
⇒ (x - 9)( x + 3) = 0
⇒ x = 9 and -3 (Answer)
Answer:
The equation that can be used to find d is 

Step-by-step explanation:
Let
d -----> the number of dogs
we know that
The linear equation that represent this situation is

Solve for d
Subtract 17 both sides


Divide by 2 both sides

Answer:
P=300cm
Step-by-step explanation:
P=4a=4.75×4=300cm