I found my notes for this exact paper and I have that first problem written. hopefully this helps
This looks like scalar matrix multiplication. The idea here is to multiply the scalar 3 by each item inside the matrix.
Doing so leads to the answer [3 -12 15 -21]
Side note: I'm assuming the matrix given to you has 1 row and 4 columns.
Answer:
The expression giving her net earnings for a day with more than 8 hours worked is X = 80 + 15H, where H means "extra hours worked".
Step-by-step explanation:
Given that Daisy works at an ice-cream parlor earning $10 per hour for the first 8 hours she works in a day, and 1.5 times her hourly wage for every extra hour she works, in order to know how much can she make in a day working more than 8 hours the following equation has to be made:
X = (8 x 10) + (H x (1.5 x 10))
X = 80 + 15H
Therefore, if Daisy works 13 hours, the equation works as follows:
X = 80 + 15x13
X = 80 + 195
X = 275
Answer:
a = 9
Step-by-step explanation:
45 = 4(a + 3) – 3
Add 3 to both sides.
48 = 4(a + 3)
Divide both sides by 4.
12 = a + 3
Subtract 3 from both sides.
9 = a
a = 9
Answer: a = 9