He made 12*40=480 dollars in total. 0.0765*480=36.72 dollars were withheld.
Answer: The book costs $10 and the pen costs $4✔️
Step-by-step explanation:
Let B the cost of the book and let P the cost of the pen.
Then we know:
The book and the pen cost $14:
B + P = $14 } Equation 1
We also know:
The cost of the book is two dollars more than twice the cost of the pen.
B = 2P + $2 } Equation 2
Now we can substitute the value of B from the equation 2 in the equation 1:
2P + $2 + P = $14
3P = $14 - $2 = $12
P = $12/3 = $4 , cost of the pen
Since we know the value of B from the equation 2, we can calculate B:
B = 2P + $2 = 2x$4 + $2 = $8 + $2 = $10 , cost of the book
Answer: The book costs $10 and the pen costs $4✔️
<h3>Verify </h3>
We can substitute these values in equations 1 and 2 and check the results:
B + P = $14 } Equation 1
$10 + $4 = $14 ✔️check!
B = 2P + $2 } Equation 2
$10 = 2x$4 + $2 = $8 + $2 = $10 ✔️check!
<h2><em>Spymore</em></h2>
By the knowledge and application of <em>algebraic</em> definitions and theorems, we find that the expression - 10 · x + 1 + 7 · x = 37 has a solution of x = 12. (Correct choice: C)
<h3>How to solve an algebraic equation</h3>
In this question we have an equation that can be solved by <em>algebraic</em> definitions and theorems, whose objective consists in clearing the variable x. Now we proceed to solve the equation for x:
- - 10 · x + 1 + 7 · x = 37 Given
- (- 10 · x + 7 · x) + 1 = 37 Associative property
- -3 · x + 1 = 37 Distributive property/Definition of subtraction
- - 3 · x = 36 Compatibility with addition/Definition of subtraction
- x = 12 Compatibility with multiplication/a/(-b) = -a/b/Definition of division/Result
By the knowledge and application of <em>algebraic</em> definitions and theorems, we find that the expression - 10 · x + 1 + 7 · x = 37 has a solution of x = 12. (Correct choice: C)
To learn more on linear equations: brainly.com/question/2263981
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Answer:
Step-by-step explanation:
(a + b)² =a² + 2ab + b²
(a -b)² = a² - 2ab + b²
1) y = (x -1)²
y= x² - 2*x*1 + 1
y = x² - 2x + 1
Ans: C
2)y = (x +4)² + 5
y = x² +2*x*4 + 4² + 5
= x² + 8x + 16 + 5
y = x² + 8x + 21
C
3) y = -(x + 9)²- 10
y = - [x² + 18x + 81] - 10
= -x² - 18x - 81 - 10
y =-x² - 18x - 91
B
4) y = 3(x + 2)² - 18
y =3 [x² + 4x + 4] - 18
y = 3x² + 12x + 12 - 18
y =3x² + 12x - 6
A
5) y = -2(x + 1)² - 16
= -2[x² + 2x + 1] -16
= -2x² - 4x - 2 - 16
y = -2x² - 4x - 18
A
6) y = 5(x + 5)²
=5[x²+ 10x + 25]
y = 5x² +50x + 125
A
7)y = (1/2)(x + 8)² - 8
y = (1/2) (x² + 16x + 64) - 8
A
8) y = (x + 3/2)² + 3/4
C
9) y = 2[x² + 16x + 64] - 5x
y = 2x² + 32x + 64 - 5x
y =2x² + 27x + 6
