Answer:
Robyn's model is logical, while Mark's is illogical.
Step-by-step explanation:
This question doesn't require calculations. What we need to do is analyze each model logically.
Mark's
Mark's representation indicates 20 instead of 2, which signifies that 200 is ten times greater than 20, making it nonsensical.
Robyn's
Robyn's representation displays 2, suggesting that 200 is 100 times greater than 2, which is not only accurate but also reasonable since 100 * 2 equals 200.
Answer:
Option 1 is valid, which entails 2 hours of walking and 12 hours of running.
Step-by-step explanation:
The equations provided are:
3w + 6r ≥ 36
3w + 6r ≤ 90
We'll assess which options comply with these equations.
1) 2 hours walking; 12 hours running
w = 2 and r = 12
3w + 6r ≥ 36
3(2) + 6(12) ≥ 36
6+72 ≥ 36
78 ≥ 36
3w + 6r ≤ 90
3(2) + 6(12) ≤ 90
6+72 ≤ 90
78 ≤ 90
Both equations are satisfied. Option 1 is valid.
2) 4 hours walking; 3 hours running
w = 4 and r = 3
3w + 6r ≥ 36
3(4) + 6(3) ≥ 36
12+18 ≥ 36
30 ≥ 36 (this does not hold since 30 < 36)
3w + 6r ≤ 90
3(4) + 6(3) ≤ 90
12+18 ≤ 90
30 ≤ 90
Thus, Option 2 is invalid.
3) 9 hours running; 12 hours walking
w = 9 and r = 12
3w + 6r ≥ 36
3(9) + 6(12) ≥ 36
27+72 ≥ 36
99 ≥ 36
3w + 6r ≤ 90
3(9) + 6(12) ≤ 90
27+72 ≤ 90
99 ≤ 90 (this does not hold since 99 > 90)
Option 3 is invalid.
4) 12 hours walking; 10 hours running
w = 12 and r = 10
3w + 6r ≥ 36
3(12) + 6(10) ≥ 36
36+60 ≥ 36
96 ≥ 36
3w + 6r ≤ 90
3(12) + 6(10) ≤ 90
36 + 60 ≤ 90
96 ≤ 90 (this does not hold since 96 > 90)
So, Option 4 is invalid.
For this context, we examine the function:
presented as:
The definition of the discriminant in a quadratic equation is provided by:
Sentences correspond to the types of roots: Different real roots, equal real roots, or distinct complex roots
Upon substituting the provided values, we arrive at
This indicates that there are two equal real roots.
To discover the intersections along the x-axis, we apply the quadratic formula:
Plugging in the values yields: 
The intersection on the x-axis is
