Answer:
8(15-m)
Step-by-step explanation:
By looking at the options, we can understand that the right one is 8(15-m), since we need to multiply the time by the number of question.
Also, we can check that result by arranging an equations usint the total time.
55 = 3m - 8(15-m)
55 = 3m - 120 + 8m
55 = 11m - 120
55 + 120 = 11m
175 = 11m
m = 175/11 = 15.91
55 = 3*15.91 - 8(15-15.91) = 47.73 - 120 + 127.28 = 55.01 ≈ 55
1. Given any triangle ABC with sides BC=a, AC=b and AB=c, the following are true :
i) the larger the angle, the larger the side in front of it, and the other way around as well. (Sine Law) Let a=20 in, then the largest angle is angle A.
ii) Given the measures of the sides of a triangle. Then the cosines of any of the angles can be found by the following formula:

2.

3. m(A) = Arccos(-0.641)≈130°,
4. Remark: We calculate Arccos with a scientific calculator or computer software unless it is one of the well known values, ex Arccos(0.5)=60°, Arccos(-0.5)=120° etc
Answer:
{x,y} = {6/5,23/10}
Step-by-step explanation:
[1] 7x + 2y = 13
[2] 4x + 4y = 14 <---------- linear equations given
Graphic Representation of the Equations : PICTURE
2y + 7x = 13 4y + 4x = 14
Solve by Substitution :
// Solve equation [2] for the variable y
[2] 4y = -4x + 14
[2] y = -x + 7/2
// Plug this in for variable y in equation [1]
[1] 7x + 2•(-x +7/2) = 13
[1] 5x = 6
// Solve equation [1] for the variable x
[1] 5x = 6
[1] x = 6/5
// By now we know this much :
x = 6/5
y = -x+7/2
// Use the x value to solve for y
y = -(6/5)+7/2 = 23/10
// Plug this in for variable y in equation [1]
[1] 7x + 2•(-x +7/2) = 13
[1] 5x = 6
// Solve equation [1] for the variable x
[1] 5x = 6
[1] x = 6/5
// By now we know this much :
x = 6/5
y = -x+7/2
// Use the x value to solve for y
y = -(6/5)+7/2 = 23/10
Answer:
Hello! answer: y = 76
Because there vertical angles they Will have the same measure therefore y = 76 Hope that helps!
Answer:
Sheila have 6 bills
Step-by-step explanation:
Suppose Sheila has x '20' dollar bills, so the total cost of her bill = $20x
Suppose Tamsin has y '10' dollar bills, so the total cost of her bill = $10y
<h3>Equation 1</h3>
<em>Sheila has a total of $50 more than Tamsin</em>
<h2><em>10y + 50 = 20x</em></h2><h2 /><h3>
Equation 2</h3>
<em>Tamsin has 1 more bill than Sheila.</em>
<h2>y = x + 1 </h2><h2 />
<em>Now solve them by putting value of x in equation </em>
10( x + 1 ) + 50 = 20x
10x + 10 + 50 = 20x
60 = 20x - 10x
10x = 60
x = 60/10
x = 6
and
y = 7
<em> </em>