Chapter 2 - Force Vectors - Section 2.4 - Addition of a System of Coplanar Forces - Problems - Page 40: 36

$F_{1} = (900\hat{i})$ $F_{2} = (530\hat{i} + 530\hat{j})$ $F_{3} = (520\hat{i} - 390\hat{j})$

We resolve the forces: $F_{1} = (900\hat{i})$ $F_{2} = (750 \times \cos 45 ° \hat{i} + 750 \times \sin 45 ° \hat {j}) = (530\hat{i} + 530\hat{j})$ $F_{3} = (650 \times 4/5\hat{i} + 650 \times 3/5 -\hat{j})=(520\hat{i} - 390\hat{j})$