<h2>x = 1/4</h2><h2>y = -2</h2><h2>______________</h2>
<h2>Known : </h2>
y = -8x
4x - y = 3
<h2>Asked: </h2>
Use the substitution method to solve the system of equations ?
<h2>Answered:</h2>
<h3>Substitution y</h3>
4x - y = 3
4x - (-8x) = 3
4x + 8x = 3
12x = 3
x = 3/12
x = 1/4
<h3>
Substitution x</h3>
4x - y = 3
4(1/4) - y = 3
4/4 - y = 3
1 - y = 3
-y = 3 - 1
-y = 2
y = -2
V1 - velocity first train
v2 - velocity second train
v2 > v1
v2 - v1 = 17 mph
We know, that:
![s_1+s_2=210 \ [miles] \\ \\ t_1=t_2=2h](https://tex.z-dn.net/?f=s_1%2Bs_2%3D210%20%5C%20%5Bmiles%5D%20%5C%5C%20%5C%5C%20t_1%3Dt_2%3D2h)
So:
NOw we've got simple system of equations:
![+\begin{cases} v_2-v_1=17 \\ v_2+v_1=105\end{cases} \\ \\ 2v_2=122 \qquad /:2 \\ \\ v_2=61 \qquad [mph] \\ \\ v_2-v_1=17 \\ \\ 61-v_1=17 \\ \\ v_1=44](https://tex.z-dn.net/?f=%2B%5Cbegin%7Bcases%7D%20v_2-v_1%3D17%20%5C%5C%20v_2%2Bv_1%3D105%5Cend%7Bcases%7D%20%5C%5C%20%5C%5C%202v_2%3D122%20%5Cqquad%20%2F%3A2%20%5C%5C%20%5C%5C%20v_2%3D61%20%5Cqquad%20%5Bmph%5D%20%5C%5C%20%5C%5C%20v_2-v_1%3D17%20%5C%5C%20%5C%5C%2061-v_1%3D17%20%5C%5C%20%5C%5C%20v_1%3D44)
Velocities of these trains are 61mph and 44mph
Answer:
A) 56.549
B) 9.425
Step-by-step explanation:
2(pi)r=56.54867
60/360x56.54867=9.425
Answer:
Do you mean an MP3 player?
Step-by-step explanation:
Answer:
B. He added 3.5 and 5 when he should have multiplied them.
Step-by-step explanation:
Let's observe Joe's steps:
- V = lwh
- 204 = 3.5 * (5) * l
Here, * means to multiply, so we're supposed to multiply 3.5 to 5, which would give you the answer 17.5. Unfortunately, look what Joe got: he obtained the value of 8.5, and if we observe, 3.5 + 5 = 8.5.
That's how we know that Joe added instead of multiplied, as he should have done. Thus, the answer is B.
