Set up and solve each equation In a magic square each row co
Solution
the given
3x-5 = 2(2x+5)
That is 3x-5 = 4x+10
-5-10 = 4x - 3x
-15 = x
Value of x = -15
10x+8 = 12x-18
That is
8 + 18 = 12x – 10x
26 = 2 x
Value of x = 13
4(x-7)= 2x-6
That is 4x-28 = 2x – 6
4x-2x = 28 – 6
2 x = 22
Value of x= 11
3(y+4) = 5y+30
That is 3y+12 = 5y+30
12- 30 =5y - 3y
That is 2y = -18
Value of y = -9
3(2y+4) = 4(y+7)-2
That is
6y + 12 = 4y +28 -2
6y - 4y = 28 -2 -12
2y = 14
Value of y = 7
6y= 10 - 4y
That is 6y+4y = 10
10 y =10
Value of y = 1
27 - 6x = 3x
That is 27 = 3x+ 6x
27 = 9x
Value of x= 3
7y+3 = 12y- 2
That is
3 + 2 = 12y – 7y
5= 5 y
Value of y = 1
2y + 2= 3y+3
That is
2- 3= 3y – 2y
Value of y = - 1
8x - (6x - 4) = 10
That is 2x – 4 =10
2x = 10+ 4 = 14
2x = 14
Value of X=7
6y= 10+4y
That is 2y = 10
Value of y = 5
6(x+7) =2(x+7)
That is 6x + 42 = 2x + 14
6x – 2x = 14 -42
4x = - 28
Value of x = -7
Two consecutive whole numbers total 17. Find the larger.
8 and 9 are two consecutive whole numbers
8 + 9 =17
Larger number is 9
Two consecutive odd numbers total 20.
Find the smaller.
9 and 11 are two consecutive odd numbers
9 + 11 = 20
Small number is 9
One number is 4 less than 3 times another. Their sum is 16. Find the smaller.
Let the two numbers are x and y
X = 3y – 4 ---- (1)
X + y = 16 ------( 2 )
From (2)
X = 16 – y ----- (3)
From (1) and (3)
16 – y = 3y – 4
16 + 4 = 3Y + Y
20 = 4 Y
Y =5
Substitute y value in (1)
We get x = 3(5)-4
X = 11
We get X = 11 and y = 5
The smaller is 5
Two consecutive odd numbers total 32. Find the smaller.
15 and 17 are two consecutive odd numbers.
15 + 17 = 32
Small number is 15.
The magic box is
Row Sum
- 15
13
11
-9
0
7
1
3
1
12
- 1
7
5
-7
4
9
9
5
15
38
Column Sum
0
30
24
0
54
Sum of row sum and column sum
Magic sum is 54
| 3x-5 = 2(2x+5) That is 3x-5 = 4x+10 -5-10 = 4x - 3x -15 = x Value of x = -15 | 10x+8 = 12x-18 That is 8 + 18 = 12x – 10x 26 = 2 x Value of x = 13 | 4(x-7)= 2x-6 That is 4x-28 = 2x – 6 4x-2x = 28 – 6 2 x = 22 Value of x= 11 | 3(y+4) = 5y+30 That is 3y+12 = 5y+30 12- 30 =5y - 3y That is 2y = -18 Value of y = -9 |
| 3(2y+4) = 4(y+7)-2 That is 6y + 12 = 4y +28 -2 6y - 4y = 28 -2 -12 2y = 14 Value of y = 7 | 6y= 10 - 4y That is 6y+4y = 10 10 y =10 Value of y = 1 | 27 - 6x = 3x That is 27 = 3x+ 6x 27 = 9x Value of x= 3 | 7y+3 = 12y- 2 That is 3 + 2 = 12y – 7y 5= 5 y Value of y = 1 |
| 2y + 2= 3y+3 That is 2- 3= 3y – 2y
Value of y = - 1 | 8x - (6x - 4) = 10 That is 2x – 4 =10 2x = 10+ 4 = 14 2x = 14 Value of X=7 | 6y= 10+4y That is 2y = 10 Value of y = 5 | 6(x+7) =2(x+7) That is 6x + 42 = 2x + 14 6x – 2x = 14 -42 4x = - 28 Value of x = -7 |
| Two consecutive whole numbers total 17. Find the larger. 8 and 9 are two consecutive whole numbers 8 + 9 =17 Larger number is 9 | Two consecutive odd numbers total 20. Find the smaller. 9 and 11 are two consecutive odd numbers 9 + 11 = 20 Small number is 9 | One number is 4 less than 3 times another. Their sum is 16. Find the smaller. Let the two numbers are x and y X = 3y – 4 ---- (1) X + y = 16 ------( 2 ) From (2) X = 16 – y ----- (3) From (1) and (3) 16 – y = 3y – 4 16 + 4 = 3Y + Y 20 = 4 Y Y =5 Substitute y value in (1) We get x = 3(5)-4 X = 11 We get X = 11 and y = 5 The smaller is 5 | Two consecutive odd numbers total 32. Find the smaller. 15 and 17 are two consecutive odd numbers. 15 + 17 = 32 Small number is 15. |




