In this case, since one equation is in the form of x=, substitution would be best for this problem. Simply plug in 4y + 8 in place of x in the second equation, solve for y, then plug that value into the first equation to find x.
Solve the following system using elimination:
{7 x + 2 y = -19 | (equation 1)
{2 y - x = 21 | (equation 2)
Add 1/7 × (equation 1) to equation 2:
{7 x + 2 y = -19 | (equation 1)
{0 x+(16 y)/7 = 128/7 | (equation 2)
Multiply equation 2 by 7/16:
{7 x + 2 y = -19 | (equation 1)
{0 x+y = 8 | (equation 2)
Subtract 2 × (equation 2) from equation 1:
{7 x+0 y = -35 | (equation 1)
{0 x+y = 8 | (equation 2)
Divide equation 1 by 7:
{x+0 y = -5 | (equation 1)
{0 x+y = 8 | (equation 2)
Collect results:
Answer: {x = -5, y = 8
(a) Yes all six trig functions exist for this point in quadrant III. The only time you'll run into problems is when either x = 0 or y = 0, due to division by zero errors. For instance, if x = 0, then tan(t) = sin(t)/cos(t) will have cos(t) = 0, as x = cos(t). you cannot have zero in the denominator. Since neither coordinate is zero, we don't have such problems.
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(b) The following functions are positive in quadrant III:
tangent, cotangent
The following functions are negative in quadrant III
cosine, sine, secant, cosecant
A short explanation is that x = cos(t) and y = sin(t). The x and y coordinates are negative in quadrant III, so both sine and cosine are negative. Their reciprocal functions secant and cosecant are negative here as well. Combining sine and cosine to get tan = sin/cos, we see that the negatives cancel which is why tangent is positive here. Cotangent is also positive for similar reasons.
Answer:
20 students
Step-by-step explanation:
If the class decreased by 15%, the students that she has now (17) represents a percentaje of:
100% - 15% = 85%
so<u> the 17 students are 85% of what she had</u>:
Students Percentage
17 ⇒ 85%
and we are looking for how many students she had 2 years ago, thus we are looking for the <u>100%</u> of students (the original number of studens). If we represent this number by x:
Students Percentage
17 ⇒ 85%
x ⇒ 100%
and we solve this problem using the <u>rule of three</u>: multiply the cross quantities on the table( 17 and 100) and then divide by the remaining amount (85):
x = 17*100/85
x = 1700/85
x=20
2 years ago she had 20 students
The missing step 2 should be;
The quantity of the sum of thirty six plus two divided by 0.5 − 14.8 ÷ 8
The missing step 6 would be that; 76 - 1.85
<h3>How to Solve Mathematical Order of Operations?</h3>
We want to know the steps to solving the expression the quantity of the sum of six squared plus two divided by the absolute value of negative 0.5 − 14.8 ÷ 8
This can be expressed as;
6² + 2 ÷ |-0.5| - 14.8 ÷ 8
Thus, the next step which is step 2 should be;
The quantity of the sum of thirty six plus two divided by 0.5 − 14.8 ÷ 8
The missing step 6 would be that;
76 - 1.85
Read more about Order of Operations at; brainly.com/question/27529825
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