Answer:
13 and 14
Step-by-step explanation:
2(x-3)=7x-31
2x-6=7x-31
-7x -7x
----------------
-5x-6=-31
+6 +6
--------------
-5x=-25
Divide by -5
x=5
3x-2(x+5)=-3+18
15
3x-2(x+5)=15
3x-2x-10=15
x-10=15
+10 +10
--------------
x=25
Answer:
x
=
−
500
b
−
50
a
+
R
±
√
250000
b
2
+
2500
a
2
−
100
a
R
+
1000
b
R
+
R
2
+
50000
a
b
2
a
b
Step-by-step explanation:
Joel = j, Mark = m, Sandra = s
j + m + s = 120
m = 3j
j = 1/2 s --> s = 2j
plug in (substitute) each letter to make it in terms of only j: j + m + s = 120
j + 3j + 2j = 120
6j = 120
6j/6 = 120/6
j = 20
now plug in for the j & s equation:
s = 2j = 2(20) = 40
Therefore Sandra has 40 coins!
