The given is that A B C D <span>x 4 = D C B A
</span><span>
Possible values of A are 1 or 2. It can't be 1 since the </span><span> </span><span>final result A is in unit place and 1 is not possible when we multiply any number by 4
</span><span>
2 B C D x </span><span>4 = </span><span>D C B 2</span>
It is clear above, that D = 8
2 B C 8 x <span>4 = </span><span>8 C B 2</span>
Possible values of B should be 1 or 2
We try B=1
2 1 C 8 x <span>4 = </span><span>8 C 1 2
</span>To find for C, you can use the equation:
(2000+100+10C+8) x 4 = 8000+100C+10+240C = 432-12 = 420
Therefore,
C = 7
So, the number is 2178.
Answer:
x ≈ 25.5°
General Formulas and Concepts:
<u>Pre-Algebra</u>
Order of Operations: BPEMDAS
- Brackets
- Parenthesis
- Exponents
- Multiplication
- Division
- Addition
- Subtraction
Equality Properties
- Multiplication Property of Equality
- Division Property of Equality
- Addition Property of Equality
- Subtract Property of Equality
<u>Trigonometry</u>
- [Right Triangles Only] SOHCAHTOA
- [Right Triangles Only] tanθ = opposite over adjacent
Step-by-step explanation:
<u>Step 1: Identify Variables</u>
Angle θ = <em>x</em>°
Opposite Leg = 10
Hypotenuse = 21
<u>Step 2: Solve for </u><em><u>x</u></em>
- Substitute [tangent]: tanx° = 10/21
- Inverse trig: x° = tan⁻¹(10/21)
- Evaluate: x = 25.4633°
- Round: x ≈ 25.5°
Answer:
a = 3
b = 2
c = 0
d = -4
Step-by-step explanation:
Form 4 equations and solve simultaneously
28 = a(2)³ + b(2)² + c(2) + d
28 = 8a + 4b + 2c + d (1)
-5 = -a + b - c + d (2)
220 = 64a + 16b + 4c + d (3)
-20 = -8a + 4b - 2c + d (4)
(1) + (4)
28 = 8a + 4b + 2c + d
-20 = -8a + 4b - 2c + d
8 = 8b + 2d
d = 4 - 4b
Equation (2)
c = -a + b + d + 5
c = -a + b + 4 - 4b+ 5
c = -a - 3b + 9
28 = 8a + 4b + 2c + d (1)
28 = 8a + 4b + 2(-a - 3b + 9) + 4 - 4b
28 = 6a - 6b + 22
6a - 6b = 6
a - b = 1
a = b + 1
220 = 64a + 16b + 4c + d (3)
220 = 64(b + 1) + 16b + 4(-b - 1 - 3b + 9) + 4 - 4b
220 = 60b + 100
60b = 120
b = 2
a = 2 + 1
a = 3
c = -3 - 3(2) + 9
c = 0
d = 4 - 4(2)
d = -4
Answer:
Step-by-step explanation:
10) The opposite sides of a parallelogram are equal. It means that
a + 15 = 3a + 11
3a - a = 15 - 11
2a = 4
a = 4/2 = 2
Also,
3b + 5 = b + 11
3b - b = 11 - 5
2b = 4
b = 4/2 = 2
11) The opposite angles of a parallelogram are congruent and the adjacent angles are supplementary. This means that
2x + 11 + x - 5 = 180
3x + 6 = 180
3x = 180 - 6 = 174
x = 174/3 = 58
Therefore,
2x + 11 = 2×58 + 11 = 127 degrees
The opposite angles of a parallelogram are congruent, therefore,
2y = 127
y = 127/2 = 63.5
12) The diagonals of a parallelogram bisect each other. This means that each diagonal is divided equally at the midpoint. Therefore
3y - 5 = y + 5
3y - y = 5 + 5
2y = 10
y = 10/2 = 5
Also,
z + 9 = 2z + 7
2z - z = 9 - 7
z = 2