Answer:
a = -2
b = -7
Explanation:
the best method to solving this system of equations would be substitution since you are given an expression that equals one of the variables you're solving for (which is b = a - 5)
to begin, plug in a - 5 for b in the equation 2a + 3b = 5.
2a + 3b = 5 ⇒ 2a + 3(a - 5) = 5
the next step is to distribute 3 to a - 5. start with distributing 3 to a, which is just multiplying 3 · a. after that, you're left with a minus sign and 5, so that sign gets attached to the 5 and makes it a -5. distribute 3 to -5, which is just multiplying 3 · -5.
2a + 3(a - 5) = 5 ⇒ 2a + 3a - 15 = 5
since you have two terms with the variable a on one side of the equation (2a and 3a), combine the two like terms.
2a + 3a - 15 = 5 ⇒ 5a - 15 = 5
add 15 to both sides of the equation. on the left side, -15 and 15 cancel each other out because -15 + 15 = 0, leaving you with only 5a. on the right side of the equation, you have 5 - 15, which equals -10.
now your equation is 5a = -10.
divide both sides of the equation by 5. on the left side of the equation, you have 5a/5, which equals 1a, or a. on the right side, you have -10/5, which equals -2.
therefore a = -2.
now plug in -2 for a in b = a - 5 in order to solve for b!
b = a - 5 ⇒ b = -2 - 5
subtract -2 - 5.
b = -2 - 5 ⇒ b = -7
therefore b = -7.
your solutions are a = -2 and b = -7 :) i hope this helps! have a great day <3