m = 4b+3 mikes age
m +b <138 mike +brother less than 138
4b+3+b<138
5b +3< 138
b< 135
b <27
The oldest the brother can be is 26
Answer:


Step-by-step explanation:
We have a positive value for the cosine of x, so we know that the value of x should be in the first quadrant (0 ≤ x ≤ 90) or in the fourth quadrant (270 ≤ x ≤ 360).
Now, let's find the value of x that gives cos(x) = 0.7252 using the inverse function of the cosine, that is, the arc cosine function.
The value of x can be calculated using:

Using this function in a calculator (you may find it as:
), we have that:

So this is the value of x in the first quadrant. To find the other value of x, in the fourth quadrant, that gives the same result, we just need to calculate 360° minus the value we found:

So the values of x are:



t - time, d - distance, v - speed
![d=39 \ mi \\ v=26 \ \frac{mi}{h} \\ \\ t=\frac{39}{26}=\frac{3 \times 13}{2 \times 13}=\frac{3}{2}=1.5 \ [h]](https://tex.z-dn.net/?f=d%3D39%20%5C%20mi%20%5C%5C%0Av%3D26%20%5C%20%5Cfrac%7Bmi%7D%7Bh%7D%20%5C%5C%20%5C%5C%0At%3D%5Cfrac%7B39%7D%7B26%7D%3D%5Cfrac%7B3%20%5Ctimes%2013%7D%7B2%20%5Ctimes%2013%7D%3D%5Cfrac%7B3%7D%7B2%7D%3D1.5%20%5C%20%5Bh%5D)
It will take
1.5 h.
Answer:
60 to nearest 10th is 60.
Step-by-step explanation:
i hope that is right if it is can b e marked brainest?