Substitution is where we first Isolate one of the unknowns, express it in terms of the other unknown, and replace the isolated unknown with the other unknown in another equation. So that each time we only need to deal with one unknown. I think you'll get a better idea here:
First name these 2 equations with 1 and 2.
4x + 5y = 7 (1)
y = 3x + 9 (2)
Since y is already isolated in (2), so we can skip the isolation step and continue to substitute.
Substitute (2) into (1).
4x + 5(3x+9) = 7
Expand.
4x + 15x + 45 = 7
Group.
19x + 45 = 7
Shift +45 to the other side and turn it into -45.
19x = 7 - 45
19x = -38
Shift x19 to the other side, turn it into /19.
X = - 38/19
X = - 2
Now we solved x already, we can just substitute x= - 2 back to equation (2).
y = 3(-2) + 9
y = - 6 + 9
y = 3
So, the answers are
x = - 2
y = 3
Answer:
-2k + 6
hope its right
-2k - (-5) + 1
You should always switch the signs to their opposites if you're mutiplying a negative such as the - (-5) Hope I make sense
-2k + 5 + 1
-2k + 6
I need more info that’s not
Answer:
Market price = Rs. 6,000
Step-by-step explanation:
Given:
Cost price = R.s 4,000
Profit after discount = 20%
Discount = 20%
Find:
Market price
Computation:
Sales price = Cost price[1+Profit after discount]
Sales price = 4,000[1+20%]
Sales price = 4,800
Market price = Sales price[100/(100 - Discount)]
Market price = 4,800[100/(100 - 20%)]
Market price = Rs. 6,000