Answer:2
Step-by-step explanation:
Given
Physics problem requires 20 min
Math problem require 10 min
suppose x question of Physics and y questions of Math are done
so according to the question
Time require for x Physics problem 
Time require for y Math problem 
so,
On solving (1) and (2)
we get 
and 
Maximum no of Physics question which can be solved is 2
D. (8, -22) is the correct answer
Step-by-step explanation:
3(t+5) = 9
3t+15 = 9
3t = -6
t = -2
2(f-7) = -10
2f - 14 = -10
2f = 4
f = 2
-(c - 9) = 4
-c + 9 = 4
-c = -5
c = 5
-6(2t + 8) = -84
-12t - 48 = -84
-12t = -36
12t = 36
t = 3
-10 (s + 2) = -57
-10s - 20 = -57
-10s = -37
s = 3.7
7(3w + 8)/3 = -9
By cross multiplication,
7(3w + 8) = -27
21w + 56 = -27
21w = -83
w = -3.95
35/5 = (F - 32)/9
7 = (F - 32)/9
By cross multiplication,
63 = F - 32
63 + 32 = F
95 = F
<em>Hope</em><em> </em><em>it</em><em> </em><em>helps</em><em>.</em>
