Answer:
The method of solving "by substitution" works by solving one of the equations (you choose which one) for one of the variables (you choose which one), and then plugging this back into the other equation, "substituting" for the chosen variable and solving for the other. Then you back-solve for the first variable.
Step-by-step explanation:
Solve the following system by substitution.
2x – 3y = –2
4x + y = 24
The idea here is to solve one of the equations for one of the variables, and plug this into the other equation. It does not matter which equation or which variable you pick. There is no right or wrong choice; the answer will be the same, regardless. But — some choices may be better than others.
For instance, in this case, can you see that it would probably be simplest to solve the second equation for "y =", since there is already a y floating around loose in the middle there? I could solve the first equation for either variable, but I'd get fractions, and solving the second equation for x would also give me fractions. It wouldn't be "wrong" to make a different choice, but it would probably be more difficult. Being lazy, I'll solve the second equation for y:
4x + y = 24
y = –4x + 24
Now I'll plug this in ("substitute it") for "y" in the first equation, and solve for x:
2x – 3(–4x + 24) = –2
2x + 12x – 72 = –2
14x = 70
x = 5
Answer:
Step-by-step explanation:
3. sin^2A + cos^2A = 1 (formula )
1 + tan^2 theta = sec^2 theta (derived from the formula sec^2 theta - tan^2 theta )
b.2x = 12 (by comparing the corresponding element)
x = 12/2
x = 6
3y = 12 (by comparing the corresponding element)
y = 12/3
y = 4
mean = sum of data / no of data
4+7+5+9+11+6 / 6
42 / 6
7
mean = 7
to find median arrange the data from ascending to descending order (from smallest to biggest)
data = 3,4,6,8,10,12
median = (N +1)/2 (N means no of data )
=6 + 1/2
=7/2
=3.5
=3 th term + 4 th term /2
=6 +8 / 2
=14/2
=7 median = 7
to find value of theta
90° + 50° + theta = 180° (sum of interior angles of a triangle)
140° + theta = 180°
theta = 180° - 140°
theta = 40°
therefore theta = 40°
Hope this helps u !!
Answer:
1/(√x-5)*(√x+5)/(√x+5)
Step-by-step explanation:
1/(√x-5)*(√x+5)/(√x+5)
The (2x+4) would be obtuse and 76 would be acute
