Toadinthehole
You talk to the child beforehand about the sort of behaviour you want to see while she tries the homework. You tell her that you understand she feels frustrated when she can't remember or understand how it was done in school. You tell her you hope if the two of you put your heads together you will figure it out and she may feel better. You tell her that you feel frustrated too, when she appears not to be listening, but just getting angry.
You ask if she is able to relax and try the homework. If not, then tell her to come back when she is ready. When she's ready, ask her if she will say something in her indoor voice like, "I am feeling overwhelmed/frustrated/angry," or, "I need a little break," when that feeling starts to build, and tell her you will take a break and then return when she is calm again. You can also use the same approach if you need a break - it is important to acknowledge you have feelings here too. This prep should all take approximately 2 minutes.
Shake on it, sound encouraging, then start by asking her to show you what the work is all about. Ask her to try to explain what she knows. Ask her what in particular she is having problems with. Try to explain the material. Work together. Smile, nod, be encouraging.
Talk to her some time when there is no maths homework looming over her about her feelings about her competence in maths. Tell her many people find it hard but making an honest effort is what counts, not whether it's all right or wrong. Tell her you hope she feels she can talk to you about her frustrations and thank her if she has managed to share anything.
It's important to be able to verbalise how everyone feels in this situation. You are not going to succeed in making any progress while the maths is front and centre and the child's feelings are going unheard. So much of getting on top of maths comes from children's positive feelings about themselves and their potential to become competent at it. It's really important to encourage a child's feeling that their parent appreciates the effort and that the end result is not all that important while it is all being worked on.
Girls are especially prone to problems with arithmetic because it is all 'right or wrong' at this stage, and they want to be 'right'. They tend not to be socialised to be risk takers and place great value on the perceived approval of the teacher that comes from being 'right' - they confuse getting sums right with being in the good books of the teacher. Maybe encourage laughter when things go wrong, when DD gets covered in mud from head to toe, when an umbrella gets swept off by the wind and you get drenched, when you burn a cake or forget to add sugar or whatever.
Get DD involved in an activity outside of school where she can take risks and be knocked down and get up again. Martial arts are ideal for promoting resilience in a safe environment.
But I would still talk to the teacher about this too OP, all the same.