Answer:
pre-image also means domain
so the value of X is 5
so 5x = 5×5
the answer is 25
The best way to multiply complicated problems mentally* is to break them into chunks.
Start with 20 times 8 to get 160, and then 8 times 5 to get 40. Add these together to get 200. 200 times 3 is 600, and 20 times 200 is 4000. Add these together to get your final answer, 4600.
In other words 8 x 20 + 8 x 5 = 200 200 x 3 + 200 x 20 = 4600
*I assumed you meant mentally, because otherwise you'd just multiply longhand, multiplying two of the three numbers and then multiplying their product with the third.
4x+2y=10 Equation 1
x-y=13 Equation 2
Solving by substitution method.
Isolate x from equation 2.
x=y+13
Substitute value of x in equation 1
4(y+13)+2y=10
4y+52+2y=10
6y+52=10
6y=-42
y=-7
Now substitute value of y in x=y+13
x=-7+13
x=6
Answer: (6,-7)
Answer:
Cost function = 40a + 500
Cost of 90 articles = $4,100
Step-by-step explanation:
The fixed cost is $500 and it will.not change regardless of production level.
The Variable cost is $40 and increases by every additional unit produced.
Assume the number of articles produced is a.
Cost function would be:
Total cost = Variable cost * Number of articles + Fixed cost
TC = 40a + 500
Using this, the cost of 90 articles is:
= 40 * 90 + 500
= $4,100
If a coral reef grows at a steady rate every week, then to find how much it grows in 12 weeks, we need to multiply the growth rate by 12 weeks. Also, since we want our answer in centimeters, we can change the growth rate to centimeters. 0.15m = 15cm
15cm * 12 = 180cm
The coral reef will grow 180cm in 12 weeks.
