Ask Singapore Homework?
Upload a photo of a Singapore homework and someone will email you the solution for free.
Question
secondary 2 | Maths
One Answer Below
Anyone can contribute an answer, even non-tutors.
How to do this question using substitution method. Thanks.
Date Posted: 4 years ago
Views: 266
2x - 7y = 5 --> Eq 1
3x + y = -4 --> Eq 2
From Eq 2,
y = -4 - 3x --> Eq 3
Sub Eq 3 into Eq 1
2x - 7 (-4 - 3x) = 5
2x + 28 + 21x = 5
2x + 21x = 5 - 28
23x = -23
x = -1
Sub x = -1 into Eq 3
y = -4 - 3 (-1)
y = -1
So, x = -1. y = -1
3x + y = -4 --> Eq 2
From Eq 2,
y = -4 - 3x --> Eq 3
Sub Eq 3 into Eq 1
2x - 7 (-4 - 3x) = 5
2x + 28 + 21x = 5
2x + 21x = 5 - 28
23x = -23
x = -1
Sub x = -1 into Eq 3
y = -4 - 3 (-1)
y = -1
So, x = -1. y = -1
See 1 Answer
done
{{ upvoteCount }} Upvotes
clear
{{ downvoteCount * -1 }} Downvotes
Make x the subject, equate the two and solve for y then x
Date Posted:
4 years ago
360 Tutoring Program