This is easy 4x+12 the answer
Answer: 21
Step-by-step explanation: 12 in 4 minutes means every minute 3 marshmallows are roasted, 4x3=12, so add three more minutes and you get 21. 7x3=21
Answer:

Step-by-step explanation:
If the quadratic equation has a root at
then when
, 



If the quadratic equation has a root at
then when
, 



Therefore, 

Answer:
0
Step-by-step explanation:
This is a horizontal line. The equation of the line is y = 10
Answer:
y = 10x + 70
slope of 10
y-intercept of 70
Step-by-step explanation: