Answer:
Step-by-step explanation:
Let the 3 numbers be 4x , 5x and 6x
4x + 6x = 5x + 55
10x = 5x + 55 Subtract 5x from both sides.
<u> 5x 5x</u>
5x = 55 Divide by 5
x = 55/5
x = 11
Therefore the numbers are
3*11 = 33
4*11 = 44
5*11 = 55
5x + y = 9....multiply by 7
10x - 7y = -18
----------------
35x + 7y = 63 (result of multiplying by 7)
10x - 7y = -18
----------------add
45x = 45
x = 45/45
x = 1
5x + y = 9
5(1) + y = 9
5 + y = 9
y = 9 - 5
y = 4
solution is : (1,4)
=========================
-4x + 9y = 9
x - 3y = -6 ....multiply by 4
----------------
-4x + 9y = 9
4x - 12y = -24 (result of multiplying by 4)
---------------add
- 3y = - 15
y = -15/-3
y = 5
x - 3y = -6
x - 3(5) = -6
x - 15 = -6
x = -6 + 15
x = 9
solution is : (9,5)
Add the 3 ratio portions together: 1 + 4 + 7 = 12
Divide total length by 12:
84/12 = 7
Multiply each ratio portion by 7:
1 x 7 = 7
4 x 7 = 28
7 x 7 = 49
The longest piece is 49 cm
Answer:
∠x = 90°
∠y = 58°
∠z = 32°
Step-by-step explanation:
he dimensions of the angles given are;
∠B = 32°
Whereby ΔABC is a right-angled triangle, and the square fits at angle A, we have;
∠A = 90°
∠B + ∠C = 90° which gives
32° + ∠C = 90°
∠C = 58°
∠x + Interior angle of the square = 180° (Sum of angles on a straight line)
∠x + 90° = 180°
∠x = 90°
∠x + ∠y + 32° = 180° (Sum of angles in a triangle)
90° + ∠y + 32° = 180°
∠y = 180 - 90° - 32° = 58°
∠y + ∠z + Interior angle of the square = 180° (Sum of angles on a straight line)
58° + ∠z +90° = 180°
∴ ∠z = 32°
∠x = 90°
∠y = 58°
∠z = 32°
Step-by-step explanation:
let's look at the last line :
x³ + 8x - 3 = Ax³ +5Ax + Bx² + 5B + Cx + D
since we find A, B, C, and D by simply comparing the factors of the various terms in x (or constants) in both sides of the equation, we need to combine a few terms on the right hand side (so that we have one term per x exponent grade).
x³ + 8x - 3 = Ax³ + (5A + C)x + Bx² + (5B + D)
by comparing now both sides, to make both sides truly equal, the factors have to be equal.
A = 1 (the same as for x³ on the left hand side).
B = 0 (a we have no x² on the left side).
5A + C = 8 (a 8 is the factor of x in the left side).
5×1 + C = 8
5 + C = 8
C = 3
5B + D = -3 (as the constant term is -3 on the left side).
5×0 + D = -3
D = -3
so, the 4th answer option is correct.
