Answer:
A
Step-by-step explanation:
You can eliminate B and D because it’s using
, but the question is asking
. So it’s either A or C. They are both written correctly, but out of the two, A is correct because just that x ≠
part of it is what makes it true.
The reason being is that the only thing that won’t make
true is when the denominator equals 0, because anything divided by 0 is undefined. So, when you plug
for x in the denominator you get:
. The
part just turns into 7, and 7 - 7 is 0. So you don’t want x to equal
.
<u>So the answer is A:</u>
,
±
There you go my friend!
I hope you understand and that this helps with your question! :)
Simplify the expression using the definition of an imaginary number i = sqrt -1
i32 = 1
i25 = i
i86 = -1
i51 = -i
a. The expression y=5x represent the number of small marbles she has.
b. The expression z=3x+2 represents the number of large marbles she has.
c. Amy has 310 small marbles, 62 medium marbles and 188 large marbles.
Step-by-step explanation:
a. Let x represent the number of medium marbles Amy has. Write an algebraic expression to represent the number of small marbles she has.
Medium marbles = x
Let,
Small marbles = y
According to given statement;
She has five times as many small marbles as medium marbles.
y = 5x Eqn 1
The expression y=5x represent the number of small marbles she has.
b. Write an algebraic expression to represent the number of large marbles she has.
Let,
Large marbles = z
The number of large marbles is two more than three times the number of medium marbles.
z = 3x+2 Eqn 2
The expression z=3x+2 represents the number of large marbles she has.
c. If Amy has a total of 560 marbles, how many of each size does she have?
x+y+z= 560 Eqn 3
Putting value of y and z from Eqn 1 and 2 in Eqn 3

Dividing both sides by 9

Putting x=62 in Eqn 1

Putting x=62 in Eqn 2

Amy has 310 small marbles, 62 medium marbles and 188 large marbles.
Keywords: linear equation, substitution method
Learn more about substitution method at:
#LearnwithBrainly
Answer:
The least score the student can get is 71 to get an overall B average at the end of the year.
Step-by-step explanation:
Let the score she needs to get be = x
We now have to take the mean of all the five subjects <em>(including x)</em> and equate it to the least score she can have to get a B grade.
Let us take the least score the student needs to get a B grade to be 85
Mean of all 5 scores =




The least score the student can get is 71 to get an overall B average at the end of the year.