Answer:
2a - b = 5
Step-by-step explanation:
4a - 2b = 10
take out the highest common factor of the left side
2(2a - b) = 10
divide both sides by two
2a - b = 10/2
2a - b = 5
1. AB is a tangent line to the circle C at point B
∴ AB⊥BC
∴ Δ ABC is a right triangle , ∠B = 90°
∴ AC² = AB² + BC²
BC = radius = 4,000
AC = 4,000 + 22,000 = 26,000
∴ AC² = AB² + BC² = 4,000² + 26,000² = 692 * 10^6
∴ AC = √( 692 * 10^6 ) ≈ 26,306 mi
=======================================================
2. <span>∠BAC = 9°
</span>
<span> Δ ABC is a right triangle , ∠B = 90°</span>
<span> ∠CBA = 90°
</span>
∴ ∠BCA = 180° - (90° + 9°) = 81°
∴ the measure of arc BD which facing the <span>satellite = 2 * 81° = 162°
</span>
while the total angel of the circle = 360°
∴ <span>The percent of the Earth’s equator which is within range of the satellite’s signal = 162/360 = 0.45 = 45%
</span>
Answer:
There are 120 students in the choir.
Step-by-step explanation:
Given that:
Number of members who participated in contest = 36
This represents 30% of the total members of choir at the school.
Let,
x be the number of total sutdents
30% of x = 36
0.3x = 36
Dividing both sides by 0.3
Hence,
There are 120 students in the choir.
Answer:
95.
Step-by-step explanation:
Step one: the first step here is to find the mean or average of the data for the six(6) weeks of total entrees. That is, we will have;
Average = (444 + 447 + 423 + 437 + 444 + 429)/ 6 = 2,624 / 6 = 437.3.
Average = 437.3.
Step two: the next step here is to determine the popularity index for the roast beef roast beef will be forecasted and that will be;
popularity index = 96 / 444.
popularity index = 21.6%.
Step three: the quantity of roast beef that should be forecasted for next Friday will be;
Popularity index × Average.
0.216 × 437.3 = 95.
Hence, the quantity of roast beef that should be forecasted for next Friday will be 95.
Basically each part of the first complex number gets multiplied by each part of the second complex number. You are multiplying 2 binomials.
(15 + 56i(7 + 4i)
= 105 + 60i + 392i + 224i^2
= 105 + 452i - 224 ( because i^2 = -1)
= - 119 + 452i