Answer:
D would be the right answer
Step-by-step explanation:
Answer:
a) 6x + 18 = 84
b) 11 yards
Step-by-step explanation:
a) You have that Jennifer made 6 identical curtains. If you chose x as the number of yards of fabric used for one curtain, you have that the total number of yards in the 6 curtains o fabric is
Furthermore, if you sum 18 yards to the 6x yards, the total amount of yards must be 84. Thus, you have the following equation:
b) Next, you solve the equation for x:
Then, 11 yards were use to make each curtain.
Answer:
(4,10)
Step-by-step explanation:
7-3= 4
5=5=10
ANSWER
83
EXPLANATION
This method makes use of a system of equations
Let x be the tens-place digit
Let y be the ones-place digit
(therefore, x and y are positive integers between 0 and 9 inclusive as they represent digits)
Then this two digit number is 10x + y
"Multiplying it by itself gives 6889" implies
(10x + y)(10x + y) = 6889
or just
(10x + y)² = 6889
Square root both sides.
Note that √(10x + y)² = 10x + y since x and y are positive and √6889 is 83
10x + y = 83
Now use the other information to make another equation
The sum of its digits is 11 so
x + y = 11
We have a system of equations as x and y must satisfy both equations for the question conditions to be met:
10x + y = 83 ... (I)
x + y = 11 ... (II)
This can be solved using elimination. Multiplying (II) by -1 to aim to get rid of y, we get
10x + y = 83 ... (I)
- x - y = -11 ... (II)
Adding the two equations, we get
(10x - x) + (y - y) = (83 - 11)
which is
9x = 72
Divide both sides by 9 to get
x = 8
This is the tens digit.
Can use x + y = 11 ... (II) to figure out value of y,
x + y = 11
⇒ y = 11 - x
⇒ y = 11 - 8
⇒ y = 3
x = 8 and y = 3
x is the tens-place digit
y is the ones-place digit
The number is 83